diff --git a/src/stdlib/SDL_memcpy.c b/src/stdlib/SDL_memcpy.c
index d8cc81bdcf..36a2bceaaa 100644
--- a/src/stdlib/SDL_memcpy.c
+++ b/src/stdlib/SDL_memcpy.c
@@ -29,7 +29,7 @@
 #endif
 void *SDL_memcpy(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len)
 {
-#ifdef __GNUC__
+#if defined(__GNUC__) && (defined(HAVE_LIBC) && HAVE_LIBC)
     /* Presumably this is well tuned for speed.
        On my machine this is twice as fast as the C code below.
      */
@@ -76,7 +76,7 @@ void *SDL_memcpy(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void
         }
     }
     return dst;
-#endif /* __GNUC__ */
+#endif /* HAVE_MEMCPY */
 }
 
 /* The optimizer on Visual Studio 2005 and later generates memcpy() and memset() calls.
diff --git a/src/stdlib/SDL_memmove.c b/src/stdlib/SDL_memmove.c
index 6758691058..38a75e0f2a 100644
--- a/src/stdlib/SDL_memmove.c
+++ b/src/stdlib/SDL_memmove.c
@@ -29,7 +29,7 @@
 #endif
 void *SDL_memmove(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len)
 {
-#ifdef __GNUC__
+#if defined(__GNUC__) && (defined(HAVE_LIBC) && HAVE_LIBC)
     /* Presumably this is well tuned for speed. */
     return __builtin_memmove(dst, src, len);
 #elif defined(HAVE_MEMMOVE)
diff --git a/src/stdlib/SDL_memset.c b/src/stdlib/SDL_memset.c
index 61ad5e8347..90ecbeedd3 100644
--- a/src/stdlib/SDL_memset.c
+++ b/src/stdlib/SDL_memset.c
@@ -29,7 +29,7 @@
 #endif
 void *SDL_memset(SDL_OUT_BYTECAP(len) void *dst, int c, size_t len)
 {
-#ifdef __GNUC__
+#if defined(__GNUC__) && (defined(HAVE_LIBC) && HAVE_LIBC)
     return __builtin_memset(dst, c, len);
 #elif defined(HAVE_MEMSET)
     return memset(dst, c, len);