[libc-commits] [libc] [libc] Expand usage of libc null checks. (PR #116262)

[Aly ElAshram via libc-commits]

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@@ -18,6 +19,10 @@ namespace LIBC_NAMESPACE_DECL {
 LLVM_LIBC_FUNCTION(void *, mempcpy,
                    (void *__restrict dst, const void *__restrict src,
                     size_t count)) {
+  if (count) {
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AlyElashram wrote:

I added a count check here , for consistency with memcpy and also since memcpy and mempcpy are well behaved at n = 0 
@lntue 

https://github.com/llvm/llvm-project/pull/116262