Rework the C strings tests to use ASSERT_SAME_TYPE. NFC there. Also change cwchar.pass.cpp to avoid constructing a couple things from zero - since apparently they can be enums in some weird C library. NFC there, either, since the values were never used.

llvm-svn: 349522
diff --git a/libcxx/test/std/strings/c.strings/cstring.pass.cpp b/libcxx/test/std/strings/c.strings/cstring.pass.cpp
index 63f86d3..22952e0 100644
--- a/libcxx/test/std/strings/c.strings/cstring.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cstring.pass.cpp
@@ -12,6 +12,8 @@
 #include <cstring>
 #include <type_traits>
 
+#include "test_macros.h"
+
 #ifndef NULL
 #error NULL not defined
 #endif
@@ -23,39 +25,40 @@
     const void* vpc = 0;
     char* cp = 0;
     const char* cpc = 0;
-    static_assert((std::is_same<decltype(std::memcpy(vp, vpc, s)), void*>::value), "");
-    static_assert((std::is_same<decltype(std::memmove(vp, vpc, s)), void*>::value), "");
-    static_assert((std::is_same<decltype(std::strcpy(cp, cpc)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strncpy(cp, cpc, s)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strcat(cp, cpc)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strncat(cp, cpc, s)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::memcmp(vpc, vpc, s)), int>::value), "");
-    static_assert((std::is_same<decltype(std::strcmp(cpc, cpc)), int>::value), "");
-    static_assert((std::is_same<decltype(std::strncmp(cpc, cpc, s)), int>::value), "");
-    static_assert((std::is_same<decltype(std::strcoll(cpc, cpc)), int>::value), "");
-    static_assert((std::is_same<decltype(std::strxfrm(cp, cpc, s)), std::size_t>::value), "");
-    static_assert((std::is_same<decltype(std::memchr(vp, 0, s)), void*>::value), "");
-    static_assert((std::is_same<decltype(std::strchr(cp, 0)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strcspn(cpc, cpc)), std::size_t>::value), "");
-    static_assert((std::is_same<decltype(std::strpbrk(cp, cpc)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strrchr(cp, 0)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strspn(cpc, cpc)), std::size_t>::value), "");
-    static_assert((std::is_same<decltype(std::strstr(cp, cpc)), char*>::value), "");
+
+    ASSERT_SAME_TYPE(void*,       decltype(std::memcpy(vp, vpc, s)));
+    ASSERT_SAME_TYPE(void*,       decltype(std::memmove(vp, vpc, s)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strcpy(cp, cpc)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strncpy(cp, cpc, s)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strcat(cp, cpc)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strncat(cp, cpc, s)));
+    ASSERT_SAME_TYPE(int,         decltype(std::memcmp(vpc, vpc, s)));
+    ASSERT_SAME_TYPE(int,         decltype(std::strcmp(cpc, cpc)));
+    ASSERT_SAME_TYPE(int,         decltype(std::strncmp(cpc, cpc, s)));
+    ASSERT_SAME_TYPE(int,         decltype(std::strcoll(cpc, cpc)));
+    ASSERT_SAME_TYPE(std::size_t, decltype(std::strxfrm(cp, cpc, s)));
+    ASSERT_SAME_TYPE(void*,       decltype(std::memchr(vp, 0, s)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strchr(cp, 0)));
+    ASSERT_SAME_TYPE(std::size_t, decltype(std::strcspn(cpc, cpc)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strpbrk(cp, cpc)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strrchr(cp, 0)));
+    ASSERT_SAME_TYPE(std::size_t, decltype(std::strspn(cpc, cpc)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strstr(cp, cpc)));
 #ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
-    static_assert((std::is_same<decltype(std::strtok(cp, cpc)), char*>::value), "");
+    ASSERT_SAME_TYPE(char*,       decltype(std::strtok(cp, cpc)));
 #endif
-    static_assert((std::is_same<decltype(std::memset(vp, 0, s)), void*>::value), "");
-    static_assert((std::is_same<decltype(std::strerror(0)), char*>::value), "");
-    static_assert((std::is_same<decltype(std::strlen(cpc)), std::size_t>::value), "");
+    ASSERT_SAME_TYPE(void*,       decltype(std::memset(vp, 0, s)));
+    ASSERT_SAME_TYPE(char*,       decltype(std::strerror(0)));
+    ASSERT_SAME_TYPE(std::size_t, decltype(std::strlen(cpc)));
 
     // These tests fail on systems whose C library doesn't provide a correct overload
     // set for strchr, strpbrk, strrchr, strstr, and memchr, unless the compiler is
     // a suitably recent version of Clang.
 #if !defined(__APPLE__) || defined(_LIBCPP_PREFERRED_OVERLOAD)
-    static_assert((std::is_same<decltype(std::memchr(vpc, 0, s)), const void*>::value), "");
-    static_assert((std::is_same<decltype(std::strchr(cpc, 0)), const char*>::value), "");
-    static_assert((std::is_same<decltype(std::strpbrk(cpc, cpc)), const char*>::value), "");
-    static_assert((std::is_same<decltype(std::strrchr(cpc, 0)), const char*>::value), "");
-    static_assert((std::is_same<decltype(std::strstr(cpc, cpc)), const char*>::value), "");
+    ASSERT_SAME_TYPE(const void*, decltype(std::memchr(vpc, 0, s)));
+    ASSERT_SAME_TYPE(const char*, decltype(std::strchr(cpc, 0)));
+    ASSERT_SAME_TYPE(const char*, decltype(std::strpbrk(cpc, cpc)));
+    ASSERT_SAME_TYPE(const char*, decltype(std::strrchr(cpc, 0)));
+    ASSERT_SAME_TYPE(const char*, decltype(std::strstr(cpc, cpc)));
 #endif
 }