[libcxx-commits] [libcxx] [libc++] Instantiate hash function externally (PR #127040)

[Louis Dionne via libcxx-commits]

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@@ -359,6 +367,9 @@
 #define _LIBCPP_AVAILABILITY_HAS_FROM_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_20
 #define _LIBCPP_AVAILABILITY_FROM_CHARS_FLOATING_POINT _LIBCPP_INTRODUCED_IN_LLVM_20_ATTRIBUTE
 
+#define _LIBCPP_AVAILABILITY_HAS_HASH _LIBCPP_INTRODUCED_IN_LLVM_21
+// No attribute, since we've had hash in the headers before
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ldionne wrote:

Please add a comment explaining what this availability macro is guarding.

Also, let's rename this to `_LIBCPP_AVAILABILITY_HAS_HASH_MEMORY` -- `HAS_HASH` is a bit too general IMO, it could be a bit confusing.

https://github.com/llvm/llvm-project/pull/127040