diff --git a/repos/base/include/cpu/string.h b/repos/base/include/cpu/string.h
index 898b0a9b57..ea6b100227 100644
--- a/repos/base/include/cpu/string.h
+++ b/repos/base/include/cpu/string.h
@@ -25,7 +25,10 @@ namespace Genode {
 	 * \param size  number of bytes to copy
 	 *
 	 * \return      number of bytes not copied
+	 *
+	 * The compiler attribute prevents array-bounds warnings with gcc 12.3.
 	 */
+	__attribute((optimize("no-tree-loop-distribute-patterns")))
 	inline size_t memcpy_cpu(void * dst, const void * src, size_t size)
 	{
 		using word_t = unsigned long;
diff --git a/repos/base/include/util/string.h b/repos/base/include/util/string.h
index af2a438d2b..8022266322 100644
--- a/repos/base/include/util/string.h
+++ b/repos/base/include/util/string.h
@@ -130,7 +130,7 @@ namespace Genode {
 	/**
 	 * Return length of null-terminated string in bytes
 	 */
-	 __attribute((optimize("no-tree-loop-distribute-patterns")))
+	__attribute((optimize("no-tree-loop-distribute-patterns")))
 	inline size_t strlen(const char *s)
 	{
 		size_t res = 0;
@@ -190,6 +190,9 @@ namespace Genode {
 	 */
 	inline void *memcpy(void *dst, const void *src, size_t size)
 	{
+		if (!size)
+			return dst;
+
 		char *d = (char *)dst, *s = (char *)src;
 		size_t i;
 
@@ -281,7 +284,7 @@ namespace Genode {
 	 * generation of a 'memset()' call in the 'while' loop
 	 * with gcc 10.
 	 */
-	 __attribute((optimize("no-tree-loop-distribute-patterns")))
+	__attribute((optimize("no-tree-loop-distribute-patterns")))
 	inline void *memset(void *dst, uint8_t i, size_t size)
 	{
 		using word_t = unsigned long;