diff options
| -rw-r--r-- | libstdc++-v3/include/bits/char_traits.h | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/libstdc++-v3/include/bits/char_traits.h b/libstdc++-v3/include/bits/char_traits.h index cfc7d0f..68ed827 100644 --- a/libstdc++-v3/include/bits/char_traits.h +++ b/libstdc++-v3/include/bits/char_traits.h @@ -263,6 +263,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION char_traits<_CharT>:: copy(char_type* __s1, const char_type* __s2, std::size_t __n) { + if (__n == 0) + return __s1; #if __cplusplus >= 202002L if (std::__is_constant_evaluated()) { @@ -271,7 +273,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION return __s1; } #endif - __builtin_memcpy(__s1, __s2, __n * sizeof(char_type)); return __s1; } @@ -293,9 +294,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION if _GLIBCXX17_CONSTEXPR (sizeof(_CharT) == 1 && __is_trivial(_CharT)) { - unsigned char __c; - __builtin_memcpy(&__c, __builtin_addressof(__a), 1); - __builtin_memset(__s, __c, __n); + if (__n) + { + unsigned char __c; + __builtin_memcpy(&__c, __builtin_addressof(__a), 1); + __builtin_memset(__s, __c, __n); + } } else { |