[libcxx-commits] [libcxx] 886b761 - [libc++][test] Fix `msvc_is_lock_free_macro_value()` (#105876)

[via libcxx-commits]

Author: Stephan T. Lavavej
Date: 2024-08-24T09:55:17-07:00
New Revision: 886b76128fba5f995c8c8e24aaa2030b59dec01a

URL: https://github.com/llvm/llvm-project/commit/886b76128fba5f995c8c8e24aaa2030b59dec01a
DIFF: https://github.com/llvm/llvm-project/commit/886b76128fba5f995c8c8e24aaa2030b59dec01a.diff

LOG: [libc++][test] Fix `msvc_is_lock_free_macro_value()` (#105876)

Followup to #99570.

* `TEST_COMPILER_MSVC` must be tested for `defined`ness, as it is
everywhere else.
+ Definition:
https://github.com/llvm/llvm-project/blob/52a7116f5c6ada234f47f7794aaf501a3692b997/libcxx/test/support/test_macros.h#L71-L72
+ Example usage:
https://github.com/llvm/llvm-project/blob/52a7116f5c6ada234f47f7794aaf501a3692b997/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp#L248
+ Fixes: `llvm-project\libcxx\test\support\atomic_helpers.h(33): fatal
error C1017: invalid integer constant expression`
* Fix bogus return type: `msvc_is_lock_free_macro_value()` returns `2`
or `0`, so it needs to return `int`.
+ Fixes: `llvm-project\libcxx\test\support\atomic_helpers.h(41): warning
C4305: 'return': truncation from 'int' to 'bool'`
* Clarity improvement: also add parens when mixing bitwise with
arithmetic operators.

Added: 
    

Modified: 
    libcxx/test/support/atomic_helpers.h

Removed: 
    


################################################################################
diff  --git a/libcxx/test/support/atomic_helpers.h b/libcxx/test/support/atomic_helpers.h
index d2f2b751cb47de..2b3a3caa06a589 100644
--- a/libcxx/test/support/atomic_helpers.h
+++ b/libcxx/test/support/atomic_helpers.h
@@ -30,15 +30,15 @@
 #  define TEST_ATOMIC_LONG_LOCK_FREE __GCC_ATOMIC_LONG_LOCK_FREE
 #  define TEST_ATOMIC_LLONG_LOCK_FREE __GCC_ATOMIC_LLONG_LOCK_FREE
 #  define TEST_ATOMIC_POINTER_LOCK_FREE __GCC_ATOMIC_POINTER_LOCK_FREE
-#elif TEST_COMPILER_MSVC
+#elif defined(TEST_COMPILER_MSVC)
 // This is lifted from STL/stl/inc/atomic on github for the purposes of
 // keeping the tests compiling for MSVC's STL. It's not a perfect solution
 // but at least the tests will keep running.
 //
 // Note MSVC's STL never produces a type that is sometimes lock free, but not always lock free.
 template <class T, size_t Size = sizeof(T)>
-constexpr bool msvc_is_lock_free_macro_value() {
-  return (Size <= 8 && (Size & Size - 1) == 0) ? 2 : 0;
+constexpr int msvc_is_lock_free_macro_value() {
+  return (Size <= 8 && (Size & (Size - 1)) == 0) ? 2 : 0;
 }
 #  define TEST_ATOMIC_CHAR_LOCK_FREE ::msvc_is_lock_free_macro_value<char>()
 #  define TEST_ATOMIC_SHORT_LOCK_FREE ::msvc_is_lock_free_macro_value<short>()