use access from gcc 11

core/klibc.c

@@ -27,19 +27,9 @@ int memcmp(const void *aptr, const void *bptr, size_t size)
 /* How many bytes are copied each iteration of the word copy loop.  */
 #define LITTLEBLOCKSIZE (sizeof (long))
 
-/* Threshhold for punting to the byte copier.  */
+/* Threshold for punting to the byte copier.  */
 #define TOO_SMALL(LEN)  ((LEN) < BIGBLOCKSIZE)
 
-void *memmove(void *dst, const void *src, size_t n)
-{
-    char *dstChar       = dst;
-    const char *srcChar = src;
-    for (size_t i = 0; i < n; i++) {
-        *(dstChar++) = *(srcChar++);
-    }
-    return dst;
-}
-
 void *memcpy(void *dst0, const void *src0, size_t len0)
 {
 #if 0
@@ -88,6 +78,16 @@ void *memcpy(void *dst0, const void *src0, size_t len0)
 #endif
 }
 
+void *memmove(void *dst, const void *src, size_t n)
+{
+    char *dstChar       = dst;
+    const char *srcChar = src;
+    for (size_t i = 0; i < n; i++) {
+        *(dstChar++) = *(srcChar++);
+    }
+    return dst;
+}
+
 void *memset(void *src, int c, size_t n)
 {
     for (char *ptr = (char *)src; n > 0; n--, ptr++) {

core/klibc.h

@@ -14,21 +14,21 @@
 /** compares the first @param n bytes (each interpreted as
  *      unsigned char) of the memory areas @param s1 and @param s2.
  */
-int memcmp(const void *s1, const void *s2, size_t n);
+__attribute__ ((access (read_only, 1, 3), access (read_only, 2, 3))) int memcmp(const void *s1, const void *s2, size_t n);
 
 /**
  * copies n bytes from memory area src to memory area dest. The memory areas may overlap
  */
-void *memmove(void *dest, const void *src, size_t n);
-void *memcpy(void *dest, const void *src, size_t n);
-void *memset(void *s, int c, size_t n);
+__attribute__ ((access (write_only, 1, 3), access (read_only, 2, 3))) void *memmove(void *dest, const void *src, size_t n);
+__attribute__ ((access (write_only, 1, 3), access (read_only, 2, 3))) void *memcpy(void *dest, const void *src, size_t n);
+__attribute__ ((access (write_only, 1, 3))) void *memset(void *s, int c, size_t n);
 char *itoa(long long int value, char *str, int base);
 int atoi(const char *str);
 void reverse(char s[]);
 int strlen(const char s[]);
-unsigned int strnlen(const char *s, size_t count);
+__attribute__ ((access (read_only, 1, 2))) unsigned int strnlen(const char *s, size_t count);
 int strcmp(const char s1[], const char s2[]);
-char *strzcpy(char *dst, const char *src, int len);
+__attribute__ ((access (read_only, 2), access (write_only, 1, 3))) char *strzcpy(char *dst, const char *src, int len);
 int puts(const char *str);
 int putc(const char str);
 int vsnprintf(char *str, size_t size, const char *format, va_list ap);

tests/test.c

@@ -496,6 +496,10 @@ void testRingBuffer()
 
 void run_test(void)
 {
+    // Example of checking thx to access attributs
+    //int a[4] = {0};
+    //int b[3] = {0};
+    //memcpy(b, a, sizeof(a));
 
     uint freemem, usedmem;
     uint afterFreemem, afterUsedmem;