Guard tests, not libc++

Author: robincaloudis

libcxx/include/__math/traits.h

@@ -79,20 +79,22 @@ _LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf
   return false;
 }
 
-#ifdef _LIBCPP_PREFERRED_OVERLOAD
 _LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(float __x) _NOEXCEPT {
   return __builtin_isinf(__x);
 }
 
-_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD bool
-isinf(double __x) _NOEXCEPT {
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI
+#ifdef _LIBCPP_PREFERRED_OVERLOAD
+_LIBCPP_PREFERRED_OVERLOAD
+#endif
+    bool
+    isinf(double __x) _NOEXCEPT {
   return __builtin_isinf(__x);
 }
 
 _LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isinf(long double __x) _NOEXCEPT {
   return __builtin_isinf(__x);
 }
-#endif
 
 // isnan
 
@@ -106,20 +108,22 @@ _LIBCPP_NODISCARD _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan
   return false;
 }
 
-#ifdef _LIBCPP_PREFERRED_OVERLOAD
 _LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(float __x) _NOEXCEPT {
   return __builtin_isnan(__x);
 }
 
-_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _LIBCPP_PREFERRED_OVERLOAD bool
-isnan(double __x) _NOEXCEPT {
+_LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI
+#ifdef _LIBCPP_PREFERRED_OVERLOAD
+_LIBCPP_PREFERRED_OVERLOAD
+#endif
+    bool
+    isnan(double __x) _NOEXCEPT {
   return __builtin_isnan(__x);
 }
 
 _LIBCPP_NODISCARD inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool isnan(long double __x) _NOEXCEPT {
   return __builtin_isnan(__x);
 }
-#endif
 
 // isnormal
 

libcxx/test/std/numerics/c.math/isinf.pass.cpp

@@ -74,7 +74,13 @@ int main(int, char**) {
   // Make sure we can call `std::isinf` with convertible types
   {
     assert(!std::isinf(ConvertibleTo<float>()));
+    // When libc++ is layered on top of Bionic's libc, `math.h` exposes a
+    // function prototype for `isinf(double)` with return type `int`. libc++
+    // can only work around it via `_LIBCPP_PREFERRED_OVERLOAD`, which is only
+    // available in modern versions of Clang, and not elsewhere.
+#if defined(TEST_COMPILER_CLANG) || !defined(__BIONIC__)
     assert(!std::isinf(ConvertibleTo<double>()));
+#endif
     assert(!std::isinf(ConvertibleTo<long double>()));
   }
 

libcxx/test/std/numerics/c.math/isnan.pass.cpp

@@ -74,7 +74,13 @@ int main(int, char**) {
   // Make sure we can call `std::isnan` with convertible types
   {
     assert(!std::isnan(ConvertibleTo<float>()));
+    // When libc++ is layered on top of Bionic's libc, `math.h` exposes a
+    // function prototype for `isnan(double)` with return type `int`. libc++
+    // can only work around it via `_LIBCPP_PREFERRED_OVERLOAD`, which is only
+    // available in modern versions of Clang, and not elsewhere.
+#if defined(TEST_COMPILER_CLANG) || !defined(__BIONIC__)
     assert(!std::isnan(ConvertibleTo<double>()));
+#endif
     assert(!std::isnan(ConvertibleTo<long double>()));
   }