[libc] [llvm] [libc][c23][fenv] Implement fetestexceptflag (PR #87828)

[Nick Desaulniers via llvm-commits]

================
@@ -8,13 +9,14 @@
 
 #include "src/fenv/fegetexceptflag.h"
 #include "src/fenv/fesetexceptflag.h"
+#include "src/fenv/fetestexceptflag.h"
 
 #include "src/__support/FPUtil/FEnvImpl.h"
 #include "test/UnitTest/Test.h"
 
 #include <fenv.h>
 
-TEST(LlvmLibcFenvTest, GetExceptFlagAndSetExceptFlag) {
+TEST(LlvmLibcFenvTest, GetExceptFlagAndSetExceptFlagAndTestExceptFlag) {
----------------
nickdesaulniers wrote:

s/GetExceptFlagAndSetExceptFlagAndTestExceptFlag/GetSetTestExceptFlag/

https://github.com/llvm/llvm-project/pull/87828