diff --git a/repos/base-fiasco/src/core/platform.cc b/repos/base-fiasco/src/core/platform.cc
index 75434a71b4..0c36da34b4 100644
--- a/repos/base-fiasco/src/core/platform.cc
+++ b/repos/base-fiasco/src/core/platform.cc
@@ -192,6 +192,11 @@ struct Region
 	{
 		return (((base + size) > start) && (base < end));
 	}
+
+	void print(Output &out) const
+	{
+		Genode::print(out, Hex_range(start, end - start));
+	}
 };
 
 
@@ -204,7 +209,8 @@ static inline void add_region(Region r, Range_allocator &alloc)
 	addr_t start = trunc_page(r.start);
 	addr_t end   = round_page(r.end);
 
-	alloc.add_range(start, end - start);
+	if (alloc.add_range(start, end - start).failed())
+		warning("unable to add range to allocator: ", r);
 }
 
 
@@ -217,7 +223,8 @@ static inline void remove_region(Region r, Range_allocator &alloc)
 	addr_t start = trunc_page(r.start);
 	addr_t end   = round_page(r.end);
 
-	alloc.remove_range(start, end - start);
+	if (alloc.remove_range(start, end - start).failed())
+		warning("unable to exclude range from allocator: ", r);
 }
 
 
@@ -297,7 +304,8 @@ void Core::Platform::_setup_mem_alloc()
 
 void Core::Platform::_setup_irq_alloc()
 {
-	_irq_alloc.add_range(0, 0x10);
+	if (_irq_alloc.add_range(0, 0x10).failed())
+		warning("unable to initialize IRQ allocator");
 }
 
 
@@ -371,15 +379,17 @@ void Core::Platform::_setup_basics()
 	/* configure applicable address space but never use page0 */
 	_vm_size  = _vm_start == 0 ? _vm_size - L4_PAGESIZE : _vm_size;
 	_vm_start = _vm_start == 0 ? L4_PAGESIZE : _vm_start;
-	_region_alloc.add_range(_vm_start, _vm_size);
+	if (_region_alloc.add_range(_vm_start, _vm_size).failed())
+		warning("unable to initialize core's virtual-memory allocator");
 
 	/* preserve stack area in core's virtual address space */
-	_region_alloc.remove_range(stack_area_virtual_base(),
-	                           stack_area_virtual_size());
+	if (_region_alloc.remove_range(stack_area_virtual_base(),
+	                               stack_area_virtual_size()).failed())
+		warning("unable to mark stack-area as used virtual memory");
 
 	/* I/O memory could be the whole user address space */
-	/* FIXME if the kernel helps to find out max address - use info here */
-	_io_mem_alloc.add_range(0, ~0);
+	if (_io_mem_alloc.add_range(0, ~0).failed())
+		warning("unable to initialize I/O-memory allocator");
 
 	/* remove KIP area from region and IO_MEM allocator */
 	remove_region(Region((addr_t)kip, (addr_t)kip + L4_PAGESIZE), _region_alloc);
@@ -450,7 +460,11 @@ Core::Platform::Platform()
 				addr_t const phys_addr = reinterpret_cast<addr_t>(phys.ptr);
 				void * const core_local_ptr = phys.ptr;
 
-				region_alloc().remove_range((addr_t)core_local_ptr, size);
+				if (region_alloc().remove_range((addr_t)core_local_ptr, size).failed()) {
+					warning("unable to mark ROM-module range for '",
+					        rom_name, "' as used virtual memory");
+					return;
+				}
 				memset(core_local_ptr, 0, size);
 				content_fn(core_local_ptr, size);
 
diff --git a/repos/base-fiasco/src/core/spec/x86/platform_x86.cc b/repos/base-fiasco/src/core/spec/x86/platform_x86.cc
index b52e1d8699..14c633fa91 100644
--- a/repos/base-fiasco/src/core/spec/x86/platform_x86.cc
+++ b/repos/base-fiasco/src/core/spec/x86/platform_x86.cc
@@ -46,9 +46,8 @@ void Platform::_setup_io_port_alloc()
 	    && fp.iofp.f == 0xf                            /* got IO ports */
 	    && fp.iofp.iosize == L4_WHOLE_IOADDRESS_SPACE
 	    && fp.iofp.iopage == 0))                       /* got whole IO space */
+		panic("Received no I/O ports from sigma0");
 
-	panic("Received no I/O ports from sigma0");
-
-	/* setup allocator */
-	_io_port_alloc.add_range(0, 0x10000);
+	if (_io_port_alloc.add_range(0, 0x10000).failed())
+		warning("unable to initialize default I/O-port range");
 }
diff --git a/repos/base-foc/src/core/platform.cc b/repos/base-foc/src/core/platform.cc
index 7b19c02d41..e1800022a4 100644
--- a/repos/base-foc/src/core/platform.cc
+++ b/repos/base-foc/src/core/platform.cc
@@ -188,6 +188,11 @@ struct Region
 	{
 		return (((base + size) > start) && (base < end));
 	}
+
+	void print(Output &out) const
+	{
+		Genode::print(out, Hex_range(start, end - start));
+	}
 };
 
 
@@ -200,7 +205,8 @@ static inline void add_region(Region r, Range_allocator &alloc)
 	addr_t const start = trunc_page(r.start);
 	addr_t const end   = round_page(r.end);
 
-	alloc.add_range(start, end - start);
+	if (alloc.add_range(start, end - start).failed())
+		warning("unable to add allocator region: ", r);
 }
 
 
@@ -213,7 +219,8 @@ static inline void remove_region(Region r, Range_allocator &alloc)
 	addr_t const start = trunc_page(r.start);
 	addr_t const end   = round_page(r.end);
 
-	alloc.remove_range(start, end - start);
+	if (alloc.remove_range(start, end - start).failed())
+		warning("unable to exclude allocator region: ", r);
 }
 
 
@@ -339,7 +346,8 @@ void Core::Platform::_setup_irq_alloc()
 	if (l4_error(res))
 		panic("could not determine number of IRQs");
 
-	_irq_alloc.add_range(0, info.nr_irqs);
+	if (_irq_alloc.add_range(0, info.nr_irqs).failed())
+		warning("unable to initialize IRQ allocator");
 }
 
 
@@ -458,18 +466,22 @@ void Core::Platform::_setup_basics()
 		_vm_start = VCPU_VIRT_EXT_END;
 	}
 
-	_region_alloc.add_range(_vm_start, _vm_size);
+	if (_region_alloc.add_range(_vm_start, _vm_size).failed())
+		warning("unable to initialize core's virtual memory");
 
 	/* preserve stack area in core's virtual address space */
-	_region_alloc.remove_range(stack_area_virtual_base(),
-	                           stack_area_virtual_size());
+	if (_region_alloc.remove_range(stack_area_virtual_base(),
+	                               stack_area_virtual_size()).failed())
+		warning("unable to exclude stack area from core-local allocator");
 
 	/* preserve utcb- area in core's virtual address space */
-	_region_alloc.remove_range((addr_t)l4_utcb(), L4_PAGESIZE * 16);
+	if (_region_alloc.remove_range((addr_t)l4_utcb(), L4_PAGESIZE * 16).failed())
+		warning("unable to exclude UTCB area from core-local allocator");
 
 	/* I/O memory could be the whole user address space */
 	/* FIXME if the kernel helps to find out max address - use info here */
-	_io_mem_alloc.add_range(0, ~0);
+	if (_io_mem_alloc.add_range(0, ~0).failed())
+		warning("unable to initialize I/O-memory allocator");
 
 	/* remove KIP and MBI area from region and IO_MEM allocator */
 	remove_region(Region((addr_t)&kip, (addr_t)&kip + L4_PAGESIZE), _region_alloc);
@@ -485,8 +497,9 @@ void Core::Platform::_setup_basics()
 	add_region(Region(img_start, img_end), _core_address_ranges());
 
 	/* requested as I/O memory by the VESA driver and ACPI (rsdp search) */
-	_io_mem_alloc.add_range   (0, 0x2000);
-	ram_alloc()  .remove_range(0, 0x2000);
+	if (_io_mem_alloc.add_range   (0, 0x2000).failed()
+	 || ram_alloc()  .remove_range(0, 0x2000).failed())
+		warning("unable to register RSDP as memory-mapped I/O range");
 }
 
 
diff --git a/repos/base-foc/src/core/rpc_cap_factory.cc b/repos/base-foc/src/core/rpc_cap_factory.cc
index 1bc541a9f5..cdfd761043 100644
--- a/repos/base-foc/src/core/rpc_cap_factory.cc
+++ b/repos/base-foc/src/core/rpc_cap_factory.cc
@@ -190,7 +190,8 @@ Cap_id_allocator::Cap_id_allocator(Allocator &alloc)
 :
 	_id_alloc(&alloc)
 {
-	_id_alloc.add_range(CAP_ID_OFFSET, unsigned(CAP_ID_RANGE) - unsigned(CAP_ID_OFFSET));
+	(void)_id_alloc.add_range(CAP_ID_OFFSET,
+	                          unsigned(CAP_ID_RANGE) - unsigned(CAP_ID_OFFSET));
 }
 
 
diff --git a/repos/base-foc/src/core/spec/x86/platform.cc b/repos/base-foc/src/core/spec/x86/platform.cc
index 935d8b571b..8ede17a451 100644
--- a/repos/base-foc/src/core/spec/x86/platform.cc
+++ b/repos/base-foc/src/core/spec/x86/platform.cc
@@ -45,7 +45,8 @@ void Platform::_setup_io_port_alloc()
 		panic("Received no I/O ports from sigma0");
 
 	/* setup allocator */
-	_io_port_alloc.add_range(0, 0x10000);
+	if (_io_port_alloc.add_range(0, 0x10000).failed())
+		warning("unable to register default I/O-port range");
 }
 
 
diff --git a/repos/base-foc/src/core/vm_session_component.cc b/repos/base-foc/src/core/vm_session_component.cc
index 46e1be3ef1..e6bdfd6867 100644
--- a/repos/base-foc/src/core/vm_session_component.cc
+++ b/repos/base-foc/src/core/vm_session_component.cc
@@ -113,8 +113,8 @@ Vm_session_component::Vm_session_component(Rpc_entrypoint &ep,
 	}
 
 	/* configure managed VM area */
-	_map.add_range(0, 0UL - 0x1000);
-	_map.add_range(0UL - 0x1000, 0x1000);
+	(void)_map.add_range(0, 0UL - 0x1000);
+	(void)_map.add_range(0UL - 0x1000, 0x1000);
 
 	caps.acknowledge();
 }
diff --git a/repos/base-hw/src/bootstrap/platform.cc b/repos/base-hw/src/bootstrap/platform.cc
index 76f5019afa..d3d58ee450 100644
--- a/repos/base-hw/src/bootstrap/platform.cc
+++ b/repos/base-hw/src/bootstrap/platform.cc
@@ -45,12 +45,18 @@ void * Platform::Ram_allocator::alloc_aligned(size_t size, unsigned align)
 }
 
 
-void Platform::Ram_allocator::add(Memory_region const & region) {
-	add_range(region.base, region.size); }
+void Platform::Ram_allocator::add(Memory_region const & region)
+{
+	if (add_range(region.base, region.size).failed())
+		Genode::warning("bootstrap failed to register RAM: ", region);
+}
 
 
-void Platform::Ram_allocator::remove(Memory_region const & region) {
-	remove_range(region.base, region.size); }
+void Platform::Ram_allocator::remove(Memory_region const & region)
+{
+	if (remove_range(region.base, region.size).failed())
+		Genode::warning("bootstrap unable to exclude RAM: ", region);
+}
 
 
 /******************
diff --git a/repos/base-hw/src/core/guest_memory.h b/repos/base-hw/src/core/guest_memory.h
index 8e4a416103..e824de612c 100644
--- a/repos/base-hw/src/core/guest_memory.h
+++ b/repos/base-hw/src/core/guest_memory.h
@@ -222,7 +222,8 @@ class Core::Guest_memory
 			_sliced_heap(ram, region_map)
 		{
 			/* configure managed VM area */
-			_map.add_range(0UL, ~0UL);
+			if (_map.add_range(0UL, ~0UL).failed())
+				warning("unable to initialize guest-memory allocator");
 		}
 
 		~Guest_memory()
diff --git a/repos/base-hw/src/core/platform.cc b/repos/base-hw/src/core/platform.cc
index dcc2feec09..5474b1366a 100644
--- a/repos/base-hw/src/core/platform.cc
+++ b/repos/base-hw/src/core/platform.cc
@@ -75,9 +75,12 @@ addr_t Platform::core_main_thread_phys_utcb()
 void Platform::_init_io_mem_alloc()
 {
 	/* add entire adress space minus the RAM memory regions */
-	_io_mem_alloc.add_range(0, ~0x0UL);
+	if (_io_mem_alloc.add_range(0, ~0x0UL).failed())
+		warning("unable to initialize I/O-memory allocator");
+
 	_boot_info().ram_regions.for_each([this] (unsigned, Hw::Memory_region const &r) {
-		_io_mem_alloc.remove_range(r.base, r.size); });
+		if (_io_mem_alloc.remove_range(r.base, r.size).failed())
+			warning("unable to exclude I/O range from RAM: ", r); });
 };
 
 
@@ -180,14 +183,21 @@ Platform::Platform()
 {
 	struct Kernel_resource : Exception { };
 
-	_core_mem_alloc.virt_alloc().add_range(Hw::Mm::core_heap().base,
-	                                       Hw::Mm::core_heap().size);
+	if (_core_mem_alloc.virt_alloc().add_range(Hw::Mm::core_heap().base,
+	                                           Hw::Mm::core_heap().size).failed())
+		warning("unable to initialize core virtual-memory allocator");
+
 	_core_virt_regions().for_each([this] (unsigned, Hw::Memory_region const & r) {
-		_core_mem_alloc.virt_alloc().remove_range(r.base, r.size); });
+		if (_core_mem_alloc.virt_alloc().remove_range(r.base, r.size).failed())
+			warning("unable to exclude core from core's virtual memory"); });
+
 	_boot_info().elf_mappings.for_each([this] (unsigned, Hw::Mapping const & m) {
-		_core_mem_alloc.virt_alloc().remove_range(m.virt(), m.size()); });
+		if (_core_mem_alloc.virt_alloc().remove_range(m.virt(), m.size()).failed())
+			warning("unable to exclude ELF mapping from core's virtual memory"); });
+
 	_boot_info().ram_regions.for_each([this] (unsigned, Hw::Memory_region const & region) {
-		_core_mem_alloc.phys_alloc().add_range(region.base, region.size); });
+		if (_core_mem_alloc.phys_alloc().add_range(region.base, region.size).failed())
+			warning("unable to register RAM region ", region); });
 
 	_init_io_port_alloc();
 
@@ -203,7 +213,8 @@ Platform::Platform()
 		if (kernel_resource) {
 			continue;
 		}
-		_irq_alloc.add_range(i, 1);
+		if (_irq_alloc.add_range(i, 1).failed())
+			warning("unable to register IRQ ", i);
 	}
 
 	_init_io_mem_alloc();
diff --git a/repos/base-hw/src/core/spec/x86_64/platform_support_common.cc b/repos/base-hw/src/core/spec/x86_64/platform_support_common.cc
index 136459a4f9..8bdc941d3e 100644
--- a/repos/base-hw/src/core/spec/x86_64/platform_support_common.cc
+++ b/repos/base-hw/src/core/spec/x86_64/platform_support_common.cc
@@ -22,7 +22,8 @@ using namespace Core;
 
 void Platform::_init_io_port_alloc()
 {
-	_io_port_alloc.add_range(0, 0x10000);
+	if (_io_port_alloc.add_range(0, 0x10000).failed())
+		warning("unable to register default I/O-port range");
 }
 
 
diff --git a/repos/base-linux/src/core/platform.cc b/repos/base-linux/src/core/platform.cc
index 84b2055a7d..e99ab00548 100644
--- a/repos/base-linux/src/core/platform.cc
+++ b/repos/base-linux/src/core/platform.cc
@@ -111,7 +111,8 @@ Core::Platform::Platform()
 	/* create resource directory under /tmp */
 	lx_mkdir(resource_path(), S_IRWXU);
 
-	_core_mem_alloc.add_range((addr_t)_core_mem, sizeof(_core_mem));
+	if (_core_mem_alloc.add_range((addr_t)_core_mem, sizeof(_core_mem)).failed())
+		warning("failed to initialize core memory allocator");
 
 	/*
 	 * Occupy the socket handle that will be used to propagate the parent
diff --git a/repos/base-linux/src/lib/base/attach_stack_area.cc b/repos/base-linux/src/lib/base/attach_stack_area.cc
index c8dd6ef6f9..96095000a3 100644
--- a/repos/base-linux/src/lib/base/attach_stack_area.cc
+++ b/repos/base-linux/src/lib/base/attach_stack_area.cc
@@ -23,14 +23,15 @@ using namespace Genode;
 
 void Platform::_attach_stack_area()
 {
-	pd._address_space.attach(pd._stack_area.dataspace(), Region_map::Attr {
+	if (pd._address_space.attach(pd._stack_area.dataspace(), Region_map::Attr {
 		.size       = stack_area_virtual_size(),
 		.offset     = { },
 		.use_at     = true,
 		.at         = stack_area_virtual_base(),
 		.executable = { },
 		.writeable  = true
-	});
+	}).failed())
+		warning("unable to attach stack area to local address space");
 
 	env_stack_area_region_map    = &pd._stack_area;
 	env_stack_area_ram_allocator = &ram;
diff --git a/repos/base-linux/src/lib/base/region_map_mmap.cc b/repos/base-linux/src/lib/base/region_map_mmap.cc
index 80411fc1ef..e30a434559 100644
--- a/repos/base-linux/src/lib/base/region_map_mmap.cc
+++ b/repos/base-linux/src/lib/base/region_map_mmap.cc
@@ -260,9 +260,9 @@ Region_map_mmap::attach(Dataspace_capability ds, Attr const &attr)
 		 * argument as the region was reserved by a PROT_NONE mapping.
 		 */
 		if (_is_attached())
-			_map_local(ds, region_size, attr.offset,
-			           true, _base + attr.at,
-			           attr.executable, true, attr.writeable);
+			if (_map_local(ds, region_size, attr.offset, true, _base + attr.at,
+			                attr.executable, true, attr.writeable).failed())
+				return Attach_error::REGION_CONFLICT;
 
 		return Range { .start = attr.at, .num_bytes = region_size };
 
@@ -317,9 +317,10 @@ Region_map_mmap::attach(Dataspace_capability ds, Attr const &attr)
 						 * We have to enforce the mapping via the 'overmap' argument as
 						 * the region was reserved by a PROT_NONE mapping.
 						 */
-						_map_local(region.dataspace(), region.size(), region.offset(),
-						           true, rm->_base + region.start() + region.offset(),
-						           attr.executable, true, attr.writeable);
+						if (_map_local(region.dataspace(), region.size(), region.offset(),
+						               true, rm->_base + region.start() + region.offset(),
+						               attr.executable, true, attr.writeable).failed())
+							return Attach_error::REGION_CONFLICT;
 					}
 
 					return Range { .start = rm->_base, .num_bytes = region_size };
@@ -398,7 +399,8 @@ void Region_map_mmap::detach(addr_t at)
 		 */
 		if (_is_attached()) {
 			lx_munmap((void *)(at + _base), region.size());
-			_reserve_local(true, at + _base, region.size());
+			if (_reserve_local(true, at + _base, region.size()).failed())
+				warning(__PRETTY_FUNCTION__, ": _reserve_local unexpectedly failed");
 		}
 
 	} else {
diff --git a/repos/base-nova/src/core/platform.cc b/repos/base-nova/src/core/platform.cc
index d6a1a9a32d..3612899175 100644
--- a/repos/base-nova/src/core/platform.cc
+++ b/repos/base-nova/src/core/platform.cc
@@ -405,7 +405,7 @@ Core::Platform::Platform()
 	/* define core's virtual address space */
 	addr_t virt_beg = _vm_base;
 	addr_t virt_end = _vm_size;
-	_core_mem_alloc.virt_alloc().add_range(virt_beg, virt_end - virt_beg);
+	(void)_core_mem_alloc.virt_alloc().add_range(virt_beg, virt_end - virt_beg);
 
 	/* exclude core image from core's virtual address allocator */
 	addr_t const core_virt_beg = trunc_page((addr_t)&_prog_img_beg);
@@ -414,29 +414,33 @@ Core::Platform::Platform()
 	addr_t const binaries_end  = round_page((addr_t)&_boot_modules_binaries_end);
 
 	size_t const core_size     = binaries_beg - core_virt_beg;
-	region_alloc().remove_range(core_virt_beg, core_size);
+
+	auto exclude_from_core = [&] (addr_t start, size_t num_bytes)
+	{
+		if (region_alloc().remove_range(start, num_bytes).failed())
+			warning("unable to exclude core-local range ", Hex_range(start, num_bytes));
+	};
+
+	exclude_from_core(core_virt_beg, core_size);
 
 	/* ROM modules are un-used by core - de-detach region */
 	addr_t const binaries_size  = binaries_end - binaries_beg;
 	unmap_local(*__main_thread_utcb, binaries_beg, binaries_size >> 12);
 
 	/* preserve Bios Data Area (BDA) in core's virtual address space */
-	region_alloc().remove_range(BDA_VIRT_ADDR, 0x1000);
+	exclude_from_core(BDA_VIRT_ADDR, 0x1000);
 
 	/* preserve stack area in core's virtual address space */
-	region_alloc().remove_range(stack_area_virtual_base(),
-	                            stack_area_virtual_size());
+	exclude_from_core(stack_area_virtual_base(), stack_area_virtual_size());
 
 	/* exclude utcb of core pager thread + empty guard pages before and after */
-	region_alloc().remove_range(CORE_PAGER_UTCB_ADDR - get_page_size(),
-	                            get_page_size() * 3);
+	exclude_from_core(CORE_PAGER_UTCB_ADDR - get_page_size(), get_page_size() * 3);
 
 	/* exclude utcb of main thread and hip + empty guard pages before and after */
-	region_alloc().remove_range((addr_t)__main_thread_utcb - get_page_size(),
-	                            get_page_size() * 4);
+	exclude_from_core((addr_t)__main_thread_utcb - get_page_size(), get_page_size() * 4);
 
 	/* exclude HIP */
-	region_alloc().remove_range(addr_t(&hip), _vm_base + _vm_size - addr_t(&hip));
+	exclude_from_core(addr_t(&hip), _vm_base + _vm_size - addr_t(&hip));
 
 	/* sanity checks */
 	addr_t check [] = {
@@ -458,7 +462,7 @@ Core::Platform::Platform()
 	}
  
 	/* initialize core's physical-memory and I/O memory allocator */
-	_io_mem_alloc.add_range(0, ~0xfffUL);
+	(void)_io_mem_alloc.add_range(0, ~0xfffUL);
 	Hip::Mem_desc *mem_desc = (Hip::Mem_desc *)mem_desc_base;
 
 	Hip::Mem_desc *boot_fb = nullptr;
@@ -495,10 +499,16 @@ Core::Platform::Platform()
 		else
 			size = trunc_page(mem_desc->addr + mem_desc->size) - base;
 
-		_io_mem_alloc.remove_range((addr_t)base, (size_t)size);
-		ram_alloc().add_range((addr_t)base, (size_t)size);
+		(void)_io_mem_alloc.remove_range((addr_t)base, (size_t)size);
+		(void)ram_alloc().add_range((addr_t)base, (size_t)size);
 	}
 
+	auto exclude_from_ram = [&] (addr_t start, size_t num_bytes)
+	{
+		if (ram_alloc().remove_range(start, num_bytes).failed())
+			warning("unable to exclude RAM range ", Hex_range(start, num_bytes));
+	};
+
 	addr_t hyp_log = 0;
 	size_t hyp_log_size = 0;
 
@@ -542,14 +552,14 @@ Core::Platform::Platform()
 		/* make acpi regions as io_mem available to platform driver */
 		if (mem_desc->type == Hip::Mem_desc::ACPI_RECLAIM_MEMORY ||
 		    mem_desc->type == Hip::Mem_desc::ACPI_NVS_MEMORY)
-			_io_mem_alloc.add_range((addr_t)base, (size_t)size);
+			(void)_io_mem_alloc.add_range((addr_t)base, (size_t)size);
 
-		ram_alloc().remove_range((addr_t)base, (size_t)size);
+		exclude_from_ram((addr_t)base, (size_t)size);
 	}
 
 	/* needed as I/O memory by the VESA driver */
-	_io_mem_alloc.add_range(0, 0x1000);
-	ram_alloc().remove_range(0, 0x1000);
+	(void)_io_mem_alloc.add_range(0, 0x1000);
+	exclude_from_ram(0, 0x1000);
 
 	/* exclude pages holding multi-boot command lines from core allocators */
 	mem_desc = (Hip::Mem_desc *)mem_desc_base;
@@ -561,8 +571,8 @@ Core::Platform::Platform()
 		curr_cmd_line_page = mem_desc->aux >> get_page_size_log2();
 		if (curr_cmd_line_page == prev_cmd_line_page) continue;
 
-		ram_alloc().remove_range(curr_cmd_line_page << get_page_size_log2(),
-		                         get_page_size() * 2);
+		exclude_from_ram(curr_cmd_line_page << get_page_size_log2(),
+		                 get_page_size() * 2);
 		prev_cmd_line_page = curr_cmd_line_page;
 	}
 
@@ -804,10 +814,10 @@ Core::Platform::Platform()
 	}
 
 	/* I/O port allocator (only meaningful for x86) */
-	_io_port_alloc.add_range(0, 0x10000);
+	(void)_io_port_alloc.add_range(0, 0x10000);
 
 	/* IRQ allocator */
-	_irq_alloc.add_range(0, hip.sel_gsi);
+	(void)_irq_alloc.add_range(0, hip.sel_gsi);
 	_gsi_base_sel = (hip.mem_desc_offset - hip.cpu_desc_offset) / hip.cpu_desc_size;
 
 	log(_rom_fs);
diff --git a/repos/base-nova/src/core/vm_session_component.cc b/repos/base-nova/src/core/vm_session_component.cc
index 9ca6467ffa..f7473a89a1 100644
--- a/repos/base-nova/src/core/vm_session_component.cc
+++ b/repos/base-nova/src/core/vm_session_component.cc
@@ -397,8 +397,8 @@ Vm_session_component::Vm_session_component(Rpc_entrypoint &ep,
 	 * Configure managed VM area. The two ranges work around the size
 	 * limitation to ULONG_MAX.
 	 */
-	_map.add_range(0, 0UL - 0x1000);
-	_map.add_range(0UL - 0x1000, 0x1000);
+	(void)_map.add_range(0, 0UL - 0x1000);
+	(void)_map.add_range(0UL - 0x1000, 0x1000);
 }
 
 
diff --git a/repos/base-okl4/src/core/platform.cc b/repos/base-okl4/src/core/platform.cc
index 072b9999c6..61a30df437 100644
--- a/repos/base-okl4/src/core/platform.cc
+++ b/repos/base-okl4/src/core/platform.cc
@@ -56,8 +56,8 @@ int Core::Platform::bi_init_mem(Okl4::uintptr_t virt_base, Okl4::uintptr_t virt_
                                 const Okl4::bi_user_data_t *data)
 {
 	Platform &p = *(Platform *)data->user_data;
-	p._core_mem_alloc.phys_alloc().add_range(phys_base, phys_end - phys_base + 1);
-	p._core_mem_alloc.virt_alloc().add_range(virt_base, virt_end - virt_base + 1);
+	(void)p._core_mem_alloc.phys_alloc().add_range(phys_base, phys_end - phys_base + 1);
+	(void)p._core_mem_alloc.virt_alloc().add_range(virt_base, virt_end - virt_base + 1);
 	return 0;
 }
 
@@ -70,7 +70,7 @@ int Core::Platform::bi_add_virt_mem(Okl4::bi_name_t, Okl4::uintptr_t base,
 		return 0;
 
 	Platform &p = *(Platform *)data->user_data;
-	p._core_mem_alloc.virt_alloc().add_range(base, end - base + 1);
+	(void)p._core_mem_alloc.virt_alloc().add_range(base, end - base + 1);
 	return 0;
 }
 
@@ -80,7 +80,7 @@ int Core::Platform::bi_add_phys_mem(Okl4::bi_name_t pool, Okl4::uintptr_t base,
 {
 	if (pool == 2) {
 		Platform &p = *(Platform *)data->user_data;
-		p._core_mem_alloc.phys_alloc().add_range(base, end - base + 1);
+		(void)p._core_mem_alloc.phys_alloc().add_range(base, end - base + 1);
 	}
 	return 0;
 }
@@ -149,19 +149,23 @@ Core::Platform::Platform()
 	Okl4::bootinfo_parse((void *)boot_info_addr, &callbacks, this);
 
 	/* initialize interrupt allocator */
-	_irq_alloc.add_range(0, 0x10);
+	if (_irq_alloc.add_range(0, 0x10).failed())
+		warning("unable to initialize IRQ allocator");
 
 	/* I/O memory could be the whole user address space */
-	_io_mem_alloc.add_range(0, ~0);
+	if (_io_mem_alloc.add_range(0, ~0).failed())
+		warning("unable to initialize I/O-memory allocator");
 
 	/* I/O port allocator (only meaningful for x86) */
-	_io_port_alloc.add_range(0, 0x10000);
+	if (_io_port_alloc.add_range(0, 0x10000).failed())
+		warning("unable to initialize I/O-port allocator");
 
 	_init_rom_modules();
 
 	/* preserve stack area in core's virtual address space */
-	_core_mem_alloc.virt_alloc().remove_range(stack_area_virtual_base(),
-	                                          stack_area_virtual_size());
+	if (_core_mem_alloc.virt_alloc().remove_range(stack_area_virtual_base(),
+	                                              stack_area_virtual_size()).failed())
+		warning("unable to mark stack area as preserved virtual memory");
 
 	_vm_start = 0x1000;
 	_vm_size  = 0xc0000000 - _vm_start;
diff --git a/repos/base-pistachio/src/core/platform.cc b/repos/base-pistachio/src/core/platform.cc
index d79a948876..67d10c92ce 100644
--- a/repos/base-pistachio/src/core/platform.cc
+++ b/repos/base-pistachio/src/core/platform.cc
@@ -282,7 +282,8 @@ static inline void add_region(Region r, Range_allocator &alloc)
 	addr_t start = trunc_page(r.start);
 	addr_t end   = round_page(r.end);
 
-	alloc.add_range(start, end - start);
+	if (alloc.add_range(start, end - start).failed())
+		warning("failed to add range to allocator: ", r);
 }
 
 
@@ -298,7 +299,8 @@ static inline void remove_region(Region r, Range_allocator &alloc)
 	addr_t start = trunc_page(r.start);
 	addr_t end   = round_page(r.end);
 
-	alloc.remove_range(start, end - start);
+	if (alloc.remove_range(start, end - start).failed())
+		warning("failed to exclude range from allocator: ", r);
 }
 
 
@@ -451,7 +453,11 @@ void Core::Platform::_setup_mem_alloc()
 }
 
 
-void Core::Platform::_setup_irq_alloc() { _irq_alloc.add_range(0, 0x10); }
+void Core::Platform::_setup_irq_alloc()
+{
+	if (_irq_alloc.add_range(0, 0x10).failed())
+		warning("unable to initialize IRQ allocator");
+}
 
 
 void Core::Platform::_setup_preemption()
@@ -496,7 +502,8 @@ void Core::Platform::_setup_basics()
 	Platform_pd::touch_utcb_space();
 
 	/* I/O memory could be the whole user address space */
-	_io_mem_alloc.add_range(0, ~0);
+	if (_io_mem_alloc.add_range(0, ~0).failed())
+		warning("unable to initialize I/O-memory allocator");
 
 	unsigned int kip_size = sizeof(L4_KernelInterfacePage_t);
 
@@ -530,10 +537,15 @@ void Core::Platform::_setup_basics()
 	}
 
 	/* configure core's virtual memory, exclude KIP, stack area */
-	_region_alloc.add_range(_vm_start, _vm_size);
-	_region_alloc.remove_range((addr_t)kip, kip_size);
-	_region_alloc.remove_range(stack_area_virtual_base(),
-	                           stack_area_virtual_size());
+	if (_region_alloc.add_range(_vm_start, _vm_size).failed())
+		warning("unable to initialize core's virtual-memory allocator");
+
+	if (_region_alloc.remove_range((addr_t)kip, kip_size).failed())
+		warning("unable to mark KIP as preserved virtual memory");
+
+	if (_region_alloc.remove_range(stack_area_virtual_base(),
+	                               stack_area_virtual_size()).failed())
+		warning("unable to mark stack area as preserved virtual memory");
 
 	/* remove KIP area from region and IO_MEM allocator */
 	remove_region(Region((addr_t)kip, (addr_t)kip + kip_size), _region_alloc);
@@ -608,7 +620,11 @@ Core::Platform::Platform()
 				addr_t const phys_addr = reinterpret_cast<addr_t>(phys.ptr);
 				void * const core_local_ptr = phys.ptr;
 
-				region_alloc().remove_range((addr_t)core_local_ptr, size);
+				if (region_alloc().remove_range((addr_t)core_local_ptr, size).failed()) {
+					warning("unable to mark ROM-module range for '",
+					        rom_name, "' as preserved virtual memory");
+					return;
+				}
 				memset(core_local_ptr, 0, size);
 				content_fn(core_local_ptr, size);
 
diff --git a/repos/base-pistachio/src/core/spec/x86/platform_x86.cc b/repos/base-pistachio/src/core/spec/x86/platform_x86.cc
index d6ff5ef11d..020e98a7ca 100644
--- a/repos/base-pistachio/src/core/spec/x86/platform_x86.cc
+++ b/repos/base-pistachio/src/core/spec/x86/platform_x86.cc
@@ -26,5 +26,6 @@ void Platform::_setup_io_port_alloc()
 {
 	/* setup allocator */
 	enum { IO_PORT_RANGE_SIZE = 0x10000 };
-	_io_port_alloc.add_range(0, IO_PORT_RANGE_SIZE);
+	if (_io_port_alloc.add_range(0, IO_PORT_RANGE_SIZE).failed())
+		warning("unable to initialize default I/O-port range");
 }
diff --git a/repos/base-sel4/src/core/platform.cc b/repos/base-sel4/src/core/platform.cc
index d6449846eb..6c2ce7ec99 100644
--- a/repos/base-sel4/src/core/platform.cc
+++ b/repos/base-sel4/src/core/platform.cc
@@ -88,14 +88,16 @@ bool Mapped_mem_allocator::_unmap_local(addr_t virt_addr, addr_t phys_addr, size
 void Core::Platform::_init_unused_phys_alloc()
 {
 	/* the lower physical ram is kept by the kernel and not usable to us */
-	_unused_phys_alloc.add_range(0x100000, 0UL - 0x100000);
+	if (_unused_phys_alloc.add_range(0x100000, 0UL - 0x100000).failed())
+		warning("unable to mark kernel-only memory as preserved");
 }
 
 
 void Core::Platform::_init_allocators()
 {
 	/* interrupt allocator */
-	_irq_alloc.add_range(0, 256);
+	if (_irq_alloc.add_range(0, 256).failed())
+		warning("unable to initialize IRQ allocator");
 
 	/*
 	 * XXX allocate intermediate CNodes for organizing the untyped pages here
@@ -109,12 +111,17 @@ void Core::Platform::_init_allocators()
 			addr_t const phys_addr = trunc_page(phys);
 			size_t const phys_size = round_page(phys - phys_addr + size);
 
-			if (device_memory)
-				_io_mem_alloc.add_range(phys_addr, phys_size);
-			else
-				_core_mem_alloc.phys_alloc().add_range(phys_addr, phys_size);
+			Hex_range const range { phys_addr, phys_size };
 
-			_unused_phys_alloc.remove_range(phys_addr, phys_size);
+			if (device_memory) {
+				if (_io_mem_alloc.add_range(phys_addr, phys_size).failed())
+					warning("failed to register I/O range: ", range);
+			} else {
+				if (_core_mem_alloc.phys_alloc().add_range(phys_addr, phys_size).failed())
+					warning("failed to register RAM range: ", range);
+			}
+			if (_unused_phys_alloc.remove_range(phys_addr, phys_size).failed())
+				warning("failed to mark range as used: ", range);
 
 			return true; /* range used by this functor */
 		});
@@ -125,7 +132,8 @@ void Core::Platform::_init_allocators()
 	 */
 
 	/* core's maximum virtual memory area */
-	_unused_virt_alloc.add_range(_vm_base, _vm_size);
+	if (_unused_virt_alloc.add_range(_vm_base, _vm_size).failed())
+		warning("unable to initialize core's virtual memory allocator");
 
 	/* remove core image from core's virtual address allocator */
 	addr_t const modules_start  = reinterpret_cast<addr_t>(&_boot_modules_binaries_begin);
@@ -133,23 +141,29 @@ void Core::Platform::_init_allocators()
 	             core_virt_end  = round_page((addr_t)&_prog_img_end);
 	addr_t const image_elf_size = core_virt_end - core_virt_beg;
 
-	_unused_virt_alloc.remove_range(core_virt_beg, image_elf_size);
-	_core_mem_alloc.virt_alloc().add_range(modules_start, core_virt_end - modules_start);
+	if (_unused_virt_alloc.remove_range(core_virt_beg, image_elf_size).failed())
+		warning("unable to mark virtual range of core image as used");
+
+	if (_core_mem_alloc.virt_alloc() .add_range(modules_start, core_virt_end - modules_start).failed())
+		warning("unable to register ROM-module range at core;s virtual memory");
 
 	/* remove initial IPC buffer from core's virtual address allocator */
 	seL4_BootInfo const &bi = sel4_boot_info();
 	addr_t const core_ipc_buffer = reinterpret_cast<addr_t>(bi.ipcBuffer);
 	addr_t const core_ipc_bsize  = 4096;
-	_unused_virt_alloc.remove_range(core_ipc_buffer, core_ipc_bsize);
+	if (_unused_virt_alloc.remove_range(core_ipc_buffer, core_ipc_bsize).failed())
+		warning("unable to mark core's IPC buffer as preserved virtual memory");
 
 	/* remove sel4_boot_info page from core's virtual address allocator */
 	addr_t const boot_info_page = reinterpret_cast<addr_t>(&bi);
 	addr_t const boot_info_size = 4096 + bi.extraLen;
-	_unused_virt_alloc.remove_range(boot_info_page, boot_info_size);
+	if (_unused_virt_alloc.remove_range(boot_info_page, boot_info_size).failed())
+		warning("unable to mark seL4 boot-info page as preserved virtual memory");
 
 	/* preserve stack area in core's virtual address space */
-	_unused_virt_alloc.remove_range(stack_area_virtual_base(),
-	                                stack_area_virtual_size());
+	if (_unused_virt_alloc.remove_range(stack_area_virtual_base(),
+	                                    stack_area_virtual_size()).failed())
+		warning("unable to mark stack area as preserved virtual memory");
 
 	if (verbose_boot_info) {
 		using Hex_range = Hex_range<addr_t>;
@@ -590,7 +604,8 @@ Core::Platform::Platform()
 			addr_t const virt_addr = (addr_t)virt.ptr;
 
 			/* add to available virtual region of core */
-			_core_mem_alloc.virt_alloc().add_range(virt_addr, virt_size);
+			if (_core_mem_alloc.virt_alloc().add_range(virt_addr, virt_size).failed())
+				warning("unable to register virtual range for dynamic allocations");
 
 			/* back region by page tables */
 			_core_vm_space.unsynchronized_alloc_page_tables(virt_addr, virt_size);
diff --git a/repos/base-sel4/src/core/spec/arm/platform.cc b/repos/base-sel4/src/core/spec/arm/platform.cc
index a2caed4f52..de141b9e95 100644
--- a/repos/base-sel4/src/core/spec/arm/platform.cc
+++ b/repos/base-sel4/src/core/spec/arm/platform.cc
@@ -91,8 +91,9 @@ void Platform::_init_core_page_table_registry()
 			if (device_memory)
 				return false;
 
-			phys_alloc_16k().add_range(phys, size);
-			_unused_phys_alloc.remove_range(phys, size);
+			if (phys_alloc_16k()  .add_range   (phys, size).failed()
+			 || _unused_phys_alloc.remove_range(phys, size).failed())
+				warning("unable to register range as RAM: ", Hex_range(phys, size));
 
 			return true;
 		},
diff --git a/repos/base-sel4/src/core/spec/x86/vm_session_component.cc b/repos/base-sel4/src/core/spec/x86/vm_session_component.cc
index c80805824e..6f7d76ec7a 100644
--- a/repos/base-sel4/src/core/spec/x86/vm_session_component.cc
+++ b/repos/base-sel4/src/core/spec/x86/vm_session_component.cc
@@ -138,8 +138,8 @@ try
 	}
 
 	/* configure managed VM area */
-	_map.add_range(0, 0UL - 0x1000);
-	_map.add_range(0UL - 0x1000, 0x1000);
+	(void)_map.add_range(0, 0UL - 0x1000);
+	(void)_map.add_range(0UL - 0x1000, 0x1000);
 
 	caps.acknowledge();
 	ram.acknowledge();
diff --git a/repos/base-sel4/src/core/spec/x86_64/platform.cc b/repos/base-sel4/src/core/spec/x86_64/platform.cc
index 1a2052b1d5..5cab6b65e8 100644
--- a/repos/base-sel4/src/core/spec/x86_64/platform.cc
+++ b/repos/base-sel4/src/core/spec/x86_64/platform.cc
@@ -87,8 +87,9 @@ void Platform::_init_core_page_table_registry()
 			if (device_memory)
 				return false;
 
-			phys_alloc_16k().add_range(phys, size);
-			_unused_phys_alloc.remove_range(phys, size);
+			if (phys_alloc_16k()  .add_range   (phys, size).failed()
+			 || _unused_phys_alloc.remove_range(phys, size).failed())
+				warning("unable to register range as RAM: ", Hex_range(phys, size));
 
 			return true;
 		},
@@ -103,7 +104,8 @@ void Platform::_init_io_ports()
 	enum { PORTS = 0x10000, PORT_FIRST = 0, PORT_LAST = PORTS - 1 };
 
 	/* I/O port allocator (only meaningful for x86) */
-	_io_port_alloc.add_range(PORT_FIRST, PORTS);
+	if (_io_port_alloc.add_range(PORT_FIRST, PORTS).failed())
+		warning("unable to register default I/O-port range");
 
 	/* create I/O port capability used by io_port_session_support.cc */
 	auto const root   = _core_cnode.sel().value();
diff --git a/repos/base/include/util/attempt.h b/repos/base/include/util/attempt.h
index 5f08a51ef2..789b1bdc92 100644
--- a/repos/base/include/util/attempt.h
+++ b/repos/base/include/util/attempt.h
@@ -17,8 +17,8 @@
 #include <util/reconstructible.h>
 
 namespace Genode {
-	template <typename, typename> struct Attempt;
-	template <typename, typename> struct Unique_attempt;
+	template <typename, typename> struct [[nodiscard]] Attempt;
+	template <typename, typename> struct [[nodiscard]] Unique_attempt;
 
 	/**
 	 * Type used for results with no return value but error conditions
@@ -86,8 +86,8 @@ class Genode::Attempt
 		bool operator == (RESULT const &rhs) const {
 			return ok()     && (_result == rhs); }
 
-		bool ok()     const { return  _ok; }
-		bool failed() const { return !_ok; }
+		[[nodiscard]] bool ok()     const { return  _ok; }
+		[[nodiscard]] bool failed() const { return !_ok; }
 
 		void print(Output &out) const
 		{
@@ -155,8 +155,8 @@ class Genode::Unique_attempt : Noncopyable
 		bool operator == (ERROR const &rhs) const {
 			return failed() && (_error == rhs); }
 
-		bool ok()     const { return  _result.constructed(); }
-		bool failed() const { return !_result.constructed(); }
+		[[nodiscard]] bool ok()     const { return  _result.constructed(); }
+		[[nodiscard]] bool failed() const { return !_result.constructed(); }
 
 		void print(auto &out) const
 		{
diff --git a/repos/base/src/core/region_map_component.cc b/repos/base/src/core/region_map_component.cc
index 1953663e4a..833d8380a3 100644
--- a/repos/base/src/core/region_map_component.cc
+++ b/repos/base/src/core/region_map_component.cc
@@ -538,7 +538,8 @@ Region_map_component::Region_map_component(Rpc_entrypoint   &ep,
 	_ds_cap(_type_deduction_helper(_ds_ep.manage(&_ds)))
 {
 	/* configure managed VM area */
-	_map.add_range(vm_start, align_addr(vm_size, get_page_size_log2()));
+	if (_map.add_range(vm_start, align_addr(vm_size, get_page_size_log2())).failed())
+		warning("unable to initialize region-map allocator");
 
 	Capability<Region_map> cap = ep.manage(this);
 	_ds.sub_rm(cap);
diff --git a/repos/base/src/include/base/internal/attached_stack_area.h b/repos/base/src/include/base/internal/attached_stack_area.h
index 5347485559..6befab5f41 100644
--- a/repos/base/src/include/base/internal/attached_stack_area.h
+++ b/repos/base/src/include/base/internal/attached_stack_area.h
@@ -35,14 +35,15 @@ struct Genode::Attached_stack_area : Expanding_region_map_client
 	{
 		Region_map_client local_rm(Pd_session_client(pd).address_space());
 
-		local_rm.attach(Expanding_region_map_client::dataspace(), Region_map::Attr {
+		if (local_rm.attach(Expanding_region_map_client::dataspace(), Region_map::Attr {
 			.size       = stack_area_virtual_size(),
 			.offset     = { },
 			.use_at     = true,
 			.at         = stack_area_virtual_base(),
 			.executable = false,
 			.writeable  = true
-		});
+		}).failed())
+			warning("unable to attach stack area to local address space");
 	}
 };
 
diff --git a/repos/base/src/lib/base/allocator_avl.cc b/repos/base/src/lib/base/allocator_avl.cc
index 5dd25548b0..655548cf1b 100644
--- a/repos/base/src/lib/base/allocator_avl.cc
+++ b/repos/base/src/lib/base/allocator_avl.cc
@@ -388,7 +388,8 @@ void Allocator_avl_base::free(void *addr)
 
 	_destroy_block(*b);
 
-	add_range(new_addr, new_size);
+	add_range(new_addr, new_size).with_error([&] (Alloc_error e) {
+		error(__PRETTY_FUNCTION__, ": unable to release freed range: ", e); });
 }
 
 
diff --git a/repos/base/src/lib/base/heap.cc b/repos/base/src/lib/base/heap.cc
index d42679b354..7a8ef35eca 100644
--- a/repos/base/src/lib/base/heap.cc
+++ b/repos/base/src/lib/base/heap.cc
@@ -328,7 +328,8 @@ Heap::Heap(Ram_allocator *ram_alloc,
 	_chunk_size(MIN_CHUNK_SIZE)
 {
 	if (static_addr)
-		_alloc->add_range((addr_t)static_addr, static_size);
+		if (_alloc->add_range((addr_t)static_addr, static_size).failed())
+			warning("unable to add static range at heap-construction time");
 }
 
 
diff --git a/repos/base/src/lib/base/thread.cc b/repos/base/src/lib/base/thread.cc
index 2d36d5229a..da75fc98ec 100644
--- a/repos/base/src/lib/base/thread.cc
+++ b/repos/base/src/lib/base/thread.cc
@@ -219,10 +219,7 @@ void Thread::free_secondary_stack(void* stack_addr)
 Thread::Stack_size_result Thread::stack_size(size_t const size)
 {
 	return _stack.convert<Stack_size_result>(
-		[&] (Stack *stack)  {
-			stack->size(size);
-			return stack->top() - stack->base();
-		},
+		[&] (Stack *stack)  { return stack->size(size); },
 		[&] (Stack_error e) { return e; });
 }
 
diff --git a/repos/base/src/lib/ldso/include/file.h b/repos/base/src/lib/ldso/include/file.h
index 4949c268ff..66447189f2 100644
--- a/repos/base/src/lib/ldso/include/file.h
+++ b/repos/base/src/lib/ldso/include/file.h
@@ -130,7 +130,8 @@ struct Linker::Elf_file : File
 		bool const binary = (start != 0);
 
 		if (binary) {
-			Region_map::r()->alloc_region_at(size, start);
+			if (Region_map::r()->alloc_region_at(size, start).failed())
+				warning("unable to allocate linker-area region for ", name);;
 			reloc_base = 0;
 			return;
 		}
diff --git a/repos/base/src/lib/ldso/include/region_map.h b/repos/base/src/lib/ldso/include/region_map.h
index 8b95c479c5..67b74a2efd 100644
--- a/repos/base/src/lib/ldso/include/region_map.h
+++ b/repos/base/src/lib/ldso/include/region_map.h
@@ -62,7 +62,8 @@ class Linker::Region_map
 				.writeable  = true
 			}).with_result(
 				[&] (Genode::Region_map::Range) {
-					_range.add_range(base, Pd_session::LINKER_AREA_SIZE);
+					if (_range.add_range(base, Pd_session::LINKER_AREA_SIZE).failed())
+						warning("failed to initialize linker-area range allocator");
 
 					if (Linker::verbose)
 						log("  ",   Hex(base),
diff --git a/repos/base/src/lib/ldso/main.cc b/repos/base/src/lib/ldso/main.cc
index 9b3c210041..ab588abac8 100644
--- a/repos/base/src/lib/ldso/main.cc
+++ b/repos/base/src/lib/ldso/main.cc
@@ -424,7 +424,8 @@ struct Linker::Binary : private Root_object, public Elf_object
 			size_t const stack_size = ((size_t(*)())addr)();
 
 			/* expand stack according to the component's needs */
-			Thread::myself()->stack_size(stack_size);
+			if (Thread::myself()->stack_size(stack_size).failed())
+				warning("unable to set initial stack size to ", stack_size);
 		}
 
 		/* call 'Component::construct' function if present */
diff --git a/repos/base/src/test/ds_ownership/main.cc b/repos/base/src/test/ds_ownership/main.cc
index db7d9cf45b..37704db18a 100644
--- a/repos/base/src/test/ds_ownership/main.cc
+++ b/repos/base/src/test/ds_ownership/main.cc
@@ -38,7 +38,8 @@ void Component::construct(Genode::Env &env)
 	ram_2.free(ds);
 
 	log("try to attach dataspace to see if it still exists");
-	env.rm().attach(ds, { });
+	if (env.rm().attach(ds, { }).failed())
+		warning("dataspace unexpectedly vanished");
 
 	log("attach operation succeeded");
 
diff --git a/repos/base/src/test/rm_nested/main.cc b/repos/base/src/test/rm_nested/main.cc
index 662fa3449c..28e79f5836 100644
--- a/repos/base/src/test/rm_nested/main.cc
+++ b/repos/base/src/test/rm_nested/main.cc
@@ -61,7 +61,11 @@ class Local_fault_handler : public Entrypoint
 			_region_map.attach(ds, {
 				.size       = { },   .offset    = { },
 				.use_at     = true,  .at        = fault.addr & ~(PAGE_SIZE - 1),
-				.executable = { },   .writeable = true });
+				.executable = { },   .writeable = true })
+			.with_result(
+				[&] (Region_map::Range) { },
+				[&] (Region_map::Attach_error) { warning("attach to sub rm failed"); }
+			);
 
 			log("returning from handle_fault");
 		}
diff --git a/repos/base/src/test/sub_rm/main.cc b/repos/base/src/test/sub_rm/main.cc
index 7cceaacdca..6aea6a6273 100644
--- a/repos/base/src/test/sub_rm/main.cc
+++ b/repos/base/src/test/sub_rm/main.cc
@@ -135,8 +135,11 @@ void Component::construct(Env &env)
 		.use_at     = true,  .at        = local_attach_addr,
 		.executable = { },   .writeable = true
 	}).convert<char *>(
-		[&] (Region_map::Range const range) { return (char *)range.start; },
-		[&] (Region_map::Attach_error)      { return nullptr; }
+		[&] (Env::Local_rm::Attachment &a) {
+			a.deallocate = false;
+			return (char *)a.ptr;
+		},
+		[&] (Env::Local_rm::Error) { return nullptr; }
 	);
 
 	log("validate pattern in sub rm");
@@ -225,7 +228,10 @@ void Component::construct(Env &env)
 		.size       = { },   .offset    = 4096,
 		.use_at     = true,  .at        = DS_SUB_OFFSET_3,
 		.executable = { },   .writeable = true
-	});
+	}).with_result(
+		[&] (Region_map::Range) { },
+		[&] (Region_map::Attach_error) { fail("RAM attachment with offset"); }
+	);
 	validate_pattern_at(test_pattern_2(), sub_rm_base + DS_SUB_OFFSET_3);
 
 	/*
@@ -238,7 +244,10 @@ void Component::construct(Env &env)
 		.size       = 2*4096,  .offset    = 4096,
 		.use_at     = true,    .at        = DS_SUB_OFFSET_4,
 		.executable = { },     .writeable = true
-	});
+	}).with_result(
+		[&] (Region_map::Range) { },
+		[&] (Region_map::Attach_error) { fail("RAM attachment with offset and size"); }
+	);
 	validate_pattern_at(test_pattern_2(), sub_rm_base + DS_SUB_OFFSET_4);
 
 	/*
diff --git a/repos/base/src/test/token/main.cc b/repos/base/src/test/token/main.cc
index 20ffd6fb1a..e138751c8a 100644
--- a/repos/base/src/test/token/main.cc
+++ b/repos/base/src/test/token/main.cc
@@ -38,10 +38,12 @@ static void test_out_of_bounds_access(Env &env)
 	Attached_ram_dataspace buf_ds(env.ram(), env.rm(), BUF_SIZE);
 
 	/* attach buffer at start of managed dataspace, leave 2nd page as guard */
-	sub_rm.attach(buf_ds.cap(), {
+	if (sub_rm.attach(buf_ds.cap(), {
 		.size       = { },   .offset    = { },
 		.use_at     = true,  .at        = 0,
-		.executable = { },   .writeable = true });
+		.executable = { },   .writeable = true
+	}).failed())
+		warning("test_out_of_bounds_access: sub_rm.attach failed");
 
 	/* locally attach managed dataspace */
 	char * const buf_ptr = env.rm().attach(sub_rm.dataspace(), {
diff --git a/repos/dde_ipxe/src/lib/dde_ipxe/dde_support.cc b/repos/dde_ipxe/src/lib/dde_ipxe/dde_support.cc
index 0d1bbfb150..218eeacdec 100644
--- a/repos/dde_ipxe/src/lib/dde_ipxe/dde_support.cc
+++ b/repos/dde_ipxe/src/lib/dde_ipxe/dde_support.cc
@@ -303,7 +303,7 @@ struct Backing_store
 	Backing_store (Genode::Allocator &alloc) : _avl(&alloc)
 	{
 		Range r = pci_drv().dma();
-		_avl.add_range(r.start, r.size);
+		(void)_avl.add_range(r.start, r.size);
 	}
 };
 
diff --git a/repos/dde_linux/src/lib/lx_kit/memory.cc b/repos/dde_linux/src/lib/lx_kit/memory.cc
index c271b665f3..91437f3a6d 100644
--- a/repos/dde_linux/src/lib/lx_kit/memory.cc
+++ b/repos/dde_linux/src/lib/lx_kit/memory.cc
@@ -94,7 +94,8 @@ void * Lx_kit::Mem_allocator::alloc(size_t const size, size_t const align,
 			 */
 			Buffer & buffer = alloc_buffer(max(size + 1, min_buffer_size));
 
-			_mem.add_range(buffer.virt_addr(), buffer.size() - 1);
+			if (_mem.add_range(buffer.virt_addr(), buffer.size() - 1).failed())
+				warning("Lx_kit::Mem_allocator unable to extend virtual allocator");
 
 			/* re-try allocation */
 			void * const virt_addr = _mem.alloc_aligned(size, (unsigned)log2(align)).convert<void *>(
diff --git a/repos/gems/src/app/trace_recorder/pcapng/backend.cc b/repos/gems/src/app/trace_recorder/pcapng/backend.cc
index 9014ebed18..7478d347a9 100644
--- a/repos/gems/src/app/trace_recorder/pcapng/backend.cc
+++ b/repos/gems/src/app/trace_recorder/pcapng/backend.cc
@@ -39,7 +39,7 @@ void Writer::start_iteration(Directory             &root,
 
 		_interface_registry.clear();
 		_buffer.clear();
-		_buffer.append<Section_header_block>();
+		(void)_buffer.append<Section_header_block>(); /* header always fits in */
 		_empty_section = true;
 	}
 	catch (Append_file::Create_failed)  {
diff --git a/repos/libports/src/lib/libc/libc_mem_alloc.cc b/repos/libports/src/lib/libc/libc_mem_alloc.cc
index 91b172a373..3e0e50c270 100644
--- a/repos/libports/src/lib/libc/libc_mem_alloc.cc
+++ b/repos/libports/src/lib/libc/libc_mem_alloc.cc
@@ -94,7 +94,8 @@ int Libc::Mem_alloc_impl::Dataspace_pool::expand(size_t size, Range_allocator *a
 	}
 
 	/* add new local address range to our local allocator */
-	alloc->add_range(range.start, range.num_bytes);
+	if (alloc->add_range(range.start, range.num_bytes).failed())
+		warning("libc is unable to extend range allocator of dataspace pool");
 
 	/* now that we have new backing store, allocate Dataspace structure */
 	return alloc->alloc_aligned(sizeof(Dataspace), 2).convert<int>(
diff --git a/repos/libports/src/lib/libdrm/ioctl_iris.cc b/repos/libports/src/lib/libdrm/ioctl_iris.cc
index a61987e953..6125229d82 100644
--- a/repos/libports/src/lib/libdrm/ioctl_iris.cc
+++ b/repos/libports/src/lib/libdrm/ioctl_iris.cc
@@ -229,7 +229,8 @@ struct Gpu::Vram
 	  _cap(gpu.alloc_vram(_elem.id(), size)),
 	  _alloc(&md_alloc)
 	{
-		_alloc.add_range(0, Genode::Dataspace_client(_cap).size());
+		if (_alloc.add_range(0, Genode::Dataspace_client(_cap).size()).failed())
+			Genode::warning("unable to initialize Gpu::Vram allocator");
 	}
 
 	struct Allocation
diff --git a/repos/libports/src/lib/libdrm/ioctl_lima.cc b/repos/libports/src/lib/libdrm/ioctl_lima.cc
index b82dbe00c0..7549733cd9 100644
--- a/repos/libports/src/lib/libdrm/ioctl_lima.cc
+++ b/repos/libports/src/lib/libdrm/ioctl_lima.cc
@@ -303,7 +303,8 @@ class Lima::Call
 				 * The end of range correspondes to LIMA_VA_RESERVE_START
 				 * in Linux minus the page we omit at the start.
 				 */
-				_alloc.add_range(0x1000, 0xfff00000ul - 0x1000);
+				if(_alloc.add_range(0x1000, 0xfff00000ul - 0x1000).failed())
+					Genode::warning("unable to initialize Gpu::Vram allocator");
 			}
 
 			Gpu::Virtual_address alloc(uint32_t size)
diff --git a/repos/os/include/os/packet_stream.h b/repos/os/include/os/packet_stream.h
index 6f705a162f..5544b247c3 100644
--- a/repos/os/include/os/packet_stream.h
+++ b/repos/os/include/os/packet_stream.h
@@ -648,14 +648,14 @@ class Genode::Packet_stream_source : private Packet_stream_base
 			                                      Ack_queue::CONSUMER))
 		{
 			/* initialize packet allocator */
-			_packet_alloc.add_range(_bulk_buffer_offset,
-			                         _bulk_buffer_size);
+			if (_packet_alloc.add_range(_bulk_buffer_offset, _bulk_buffer_size).failed())
+				warning("unable to initialize packet-stream source allocator");
 		}
 
 		~Packet_stream_source()
 		{
-			_packet_alloc.remove_range(_bulk_buffer_offset,
-			                            _bulk_buffer_size);
+			if (_packet_alloc.remove_range(_bulk_buffer_offset, _bulk_buffer_size).failed())
+				warning("packet-stream source allocator in bad state at destruction time");
 		}
 
 		using Packet_stream_base::packet_valid;
diff --git a/repos/os/src/app/trace_logger/main.cc b/repos/os/src/app/trace_logger/main.cc
index fa0ffa412e..46faf386b5 100644
--- a/repos/os/src/app/trace_logger/main.cc
+++ b/repos/os/src/app/trace_logger/main.cc
@@ -181,7 +181,9 @@ class Main
 			{
 				policy.id.with_result(
 					[&] (Trace::Policy_id const policy_id) {
-						_trace.trace(id, policy_id, buffer_size); },
+						if (_trace.trace(id, policy_id, buffer_size).failed())
+							warning("failed to enable tracing with policy '", policy_name, "'");
+					},
 					[&] (auto) {
 						warning("skip tracing because of invalid policy '", policy_name, "'");
 					});
diff --git a/repos/os/src/driver/acpi/memory.h b/repos/os/src/driver/acpi/memory.h
index 6064079bb2..39e10168a8 100644
--- a/repos/os/src/driver/acpi/memory.h
+++ b/repos/os/src/driver/acpi/memory.h
@@ -110,7 +110,8 @@ class Acpi::Memory
 
 		Memory(Env &env, Allocator &heap) : _env(env), _heap(heap)
 		{
-			_range.add_range(0, ~0UL);
+			if (_range.add_range(0, ~0UL).failed())
+				warning("unable to initialize Memory::_range");
 		}
 
 		addr_t map_region(addr_t const req_base, addr_t const req_size)
@@ -182,20 +183,23 @@ class Acpi::Memory
 
 			_range.construct_metadata((void *)loop_region.base(), _env, loop_region);
 
+			Io_mem &io_mem = *_range.metadata((void *)loop_region.base());
+
 			/*
 			 * We attach the I/O memory dataspace into a virtual-memory window,
 			 * which starts at _io_region.base(). Therefore, the attachment
 			 * address is the offset of loop_region.base() from
 			 * _io_region.base().
 			 */
-			_acpi_window.attach(_range.metadata((void *)loop_region.base())->connection->dataspace(), {
+			if (_acpi_window.attach(io_mem.connection->dataspace(), {
 				.size       = loop_region.size(),
 				.offset     = { },
 				.use_at     = true,
 				.at         = loop_region.base() - _io_region->base(),
 				.executable = { },
 				.writeable  = { }
-			});
+			}).failed())
+				warning("unable to attach io_mem to ACPI window: ", io_mem.region);
 
 			return _acpi_ptr(req_base);
 		}
diff --git a/repos/os/src/driver/platform/dma_allocator.cc b/repos/os/src/driver/platform/dma_allocator.cc
index 11efd0186a..81325ac559 100644
--- a/repos/os/src/driver/platform/dma_allocator.cc
+++ b/repos/os/src/driver/platform/dma_allocator.cc
@@ -121,7 +121,8 @@ Dma_allocator::Dma_allocator(Allocator       & md_alloc,
 {
 	/* 0x1000 - 4GB */
 	enum { DMA_SIZE = 0xffffe000 };
-	_dma_alloc.add_range(0x1000, DMA_SIZE);
+	if (_dma_alloc.add_range(0x1000, DMA_SIZE).failed())
+		warning("unable to add 0x1000 range to DMA allocator");
 
 	/*
 	 * Interrupt address range is special handled and in general not
@@ -130,7 +131,8 @@ Dma_allocator::Dma_allocator(Allocator       & md_alloc,
 	 * (March 2023, Revision 4.1)
 	 */
 	enum { IRQ_RANGE_BASE = 0xfee00000u, IRQ_RANGE_SIZE = 0x100000 };
-	_dma_alloc.remove_range(IRQ_RANGE_BASE, IRQ_RANGE_SIZE);
+	if (_dma_alloc.remove_range(IRQ_RANGE_BASE, IRQ_RANGE_SIZE).failed())
+		warning("unable to exclude IRQ range from DMA allocator");
 }
 
 
diff --git a/repos/os/src/server/cpu_balancer/trace.h b/repos/os/src/server/cpu_balancer/trace.h
index 028a7a148b..938ae3c279 100644
--- a/repos/os/src/server/cpu_balancer/trace.h
+++ b/repos/os/src/server/cpu_balancer/trace.h
@@ -59,12 +59,8 @@ class Cpu::Trace
 			_trace.destruct();
 			_trace.construct(_env, _ram_quota, _arg_quota);
 
-			/*
-			 * Explicitly re-trigger import of subjects. Otherwise
-			 * stored trace ids are not valid if used with subject_info(id)
-			 * and we get exception thrown about unknown ids.
-			 */
-			_trace->_retry<Genode::Trace::Session::Alloc_rpc_error>([&] {
+			/* explicitly re-trigger import of subjects */
+			(void)_trace->_retry<Genode::Trace::Session::Alloc_rpc_error>([&] {
 				return _trace->call<Genode::Trace::Session::Rpc_subjects>(); });
 
 			_subject_id_reread ++;
diff --git a/repos/os/src/server/vmm/config.h b/repos/os/src/server/vmm/config.h
index a59223f6c8..47d0e1dfe3 100644
--- a/repos/os/src/server/vmm/config.h
+++ b/repos/os/src/server/vmm/config.h
@@ -120,8 +120,11 @@ class Vmm::Config
 
 	public:
 
-		Config(Heap & heap) : _heap(heap) {
-			_mmio_alloc.add_range(VIRTIO_MMIO_START, VIRTIO_MMIO_SIZE); }
+		Config(Heap & heap) : _heap(heap)
+		{
+			if (_mmio_alloc.add_range(VIRTIO_MMIO_START, VIRTIO_MMIO_SIZE).failed())
+				warning("failed to add virtio MMIO range");
+		}
 
 		bool initrd() const { return _initrd_name.valid(); }
 
diff --git a/repos/pc/src/driver/platform/pc/expanding_page_table_allocator.h b/repos/pc/src/driver/platform/pc/expanding_page_table_allocator.h
index 1732af7cd4..ae387f5159 100644
--- a/repos/pc/src/driver/platform/pc/expanding_page_table_allocator.h
+++ b/repos/pc/src/driver/platform/pc/expanding_page_table_allocator.h
@@ -75,11 +75,11 @@ class Driver::Expanding_page_table_allocator
 						  _virt_addr((addr_t)_dataspace.local_addr<void>()),
 						  _phys_addr(pd.dma_addr(_dataspace.cap()))
 						{
-							_range_alloc.add_range(_phys_addr, size);
+							(void)_range_alloc.add_range(_phys_addr, size);
 						}
 
 						~Element() {
-							_range_alloc.remove_range(_phys_addr, _dataspace.size()); }
+							(void)_range_alloc.remove_range(_phys_addr, _dataspace.size()); }
 
 						bool matches(addr_t pa)
 						{
diff --git a/repos/ports/src/virtualbox6/sup_gmm.cc b/repos/ports/src/virtualbox6/sup_gmm.cc
index 15b73efe2b..633accc249 100644
--- a/repos/ports/src/virtualbox6/sup_gmm.cc
+++ b/repos/ports/src/virtualbox6/sup_gmm.cc
@@ -61,7 +61,8 @@ void Sup::Gmm::_add_one_slice()
 
 	_slices[_slice_index(Offset{attach_base})] = ds;
 
-	_alloc.add_range(attach_base, slice_size);
+	if (_alloc.add_range(attach_base, slice_size).failed())
+		warning("unable to to add Gmm slice to range allocator");
 
 	/* update allocation size */
 	_size_pages = { (attach_base + slice_size) >> PAGE_SHIFT };