Address philnik777's comment regarding ABI

winner245 · winner245 · commit 853fe17e126f · 2025-02-19T18:50:07.000-05:00
diff --git a/libcxx/include/bitset b/libcxx/include/bitset
@@ -329,6 +329,8 @@ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void __bitset<_N_words, _Siz
   for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
     *__p = ~*__p;
   // do last partial word
+  // Ensure trailing padding bits are zeroed as part of the ABI for consistent hashing behavior. std::hash<bitset>
+  // assumes trailing bits are zeroed; otherwise, identical bitsets could hash differently.
   if (__n > 0)
     *__p ^= (__storage_type(1) << __n) - 1;
 }

Original file line number	Diff line number	Diff line change
`@@ -329,6 +329,8 @@ _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 void __bitset<_N_words, _Siz`
`329`	`329`	`for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)`
`330`	`330`	`__p = ~__p;`
`331`	`331`	`// do last partial word`
	`332`	`+ // Ensure trailing padding bits are zeroed as part of the ABI for consistent hashing behavior. std::hash<bitset>`
	`333`	`+ // assumes trailing bits are zeroed; otherwise, identical bitsets could hash differently.`
`332`	`334`	`if (__n > 0)`
`333`	`335`	`*__p ^= (__storage_type(1) << __n) - 1;`
`334`	`336`	`}`