diff --git a/config/debug/gdb.in b/config/debug/gdb.in
index aa3235ed..b0b9d294 100644
--- a/config/debug/gdb.in
+++ b/config/debug/gdb.in
@@ -21,6 +21,13 @@ config GDB_DEP_CXX11
     depends on !CONFIGURE_has_cxx11
     select GDB_REQUIRE_older_than_8_0
 
+# GDB10 and newer require std::future<> which was not implemented on some
+# architectures until GCC9; see GCC PR 64735.
+config GDB_DEP_NO_STD_FUTURE
+    def_bool y
+    depends on !GCC_9_or_later
+    select GDB_REQUIRE_older_than_10_2
+
 # Does GDB need ps_get_thread_area with const qualifier?
 config GDB_CONST_GET_THREAD_AREA
     bool
diff --git a/samples/sparc-leon-linux-uclibc/crosstool.config b/samples/sparc-leon-linux-uclibc/crosstool.config
index 411ea7f4..0fd6360e 100644
--- a/samples/sparc-leon-linux-uclibc/crosstool.config
+++ b/samples/sparc-leon-linux-uclibc/crosstool.config
@@ -8,7 +8,6 @@ CT_KERNEL_LINUX=y
 CT_LINUX_V_3_10=y
 CT_LIBC_UCLIBC_NG=y
 CT_LIBC_UCLIBC_CONFIG_FILE="${CT_LIB_DIR}/samples/${CT_TARGET}/${CT_LIBC}.config"
-CT_LIBC_UCLIBC_IPV6=y
 CT_GCC_V_6=y
 CT_CC_GCC_EXTRA_CONFIG_ARRAY="--disable-libitm"
 CT_CC_LANG_CXX=y