Fix FBString with MSVC

[folly.git] / folly / FBString.h

diff --git a/folly/FBString.h b/folly/FBString.h
index 45710dc79bbcb40bd52c1f47806d58c831891bcb..0ff4ba9e6a05bd4a3895973f641507477a93ccb7 100644 (file)
--- a/folly/FBString.h
+++ b/folly/FBString.h
@@ -56,6 +56,7 @@
 #include <folly/Hash.h>
 #include <folly/Malloc.h>
 #include <folly/Traits.h>
+#include <folly/portability/BitsFunctexcept.h>
 
 #if FOLLY_HAVE_DEPRECATED_ASSOC
 #ifdef _GLIBCXX_SYMVER
@@ -79,13 +80,13 @@
 #define FBSTRING_UNLIKELY(x) (x)
 #endif
 
-#pragma GCC diagnostic push
+FOLLY_PUSH_WARNING
 // Ignore shadowing warnings within this file, so includers can use -Wshadow.
-#pragma GCC diagnostic ignored "-Wshadow"
+FOLLY_GCC_DISABLE_WARNING("-Wshadow")
 // GCC 4.9 has a false positive in setSmallSize (probably
 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59124), disable
 // compile-time array bound checking.
-#pragma GCC diagnostic ignored "-Warray-bounds"
+FOLLY_GCC_DISABLE_WARNING("-Warray-bounds")
 
 // FBString cannot use throw when replacing std::string, though it may still
 // use std::__throw_*
@@ -1234,10 +1235,19 @@ public:
   // value_type overload is dangerous, so we're explicitly deleting
   // any overloads of operator= that could implicitly convert to
   // value_type.
+  // Note that we do need to explicitly specify the template types because
+  // otherwise MSVC 2017 will aggressively pre-resolve value_type to
+  // traits_type::char_type, which won't compare as equal when determining
+  // which overload the implementation is referring to.
+  // Also note that MSVC 2015 Update 3 requires us to explicitly specify the
+  // namespace in-which to search for basic_fbstring, otherwise it tries to
+  // look for basic_fbstring::basic_fbstring, which is just plain wrong.
   template <typename TP>
   typename std::enable_if<
-      std::is_same<typename std::decay<TP>::type, value_type>::value,
-      basic_fbstring&>::type
+      std::is_same<
+          typename std::decay<TP>::type,
+          typename folly::basic_fbstring<E, T, A, Storage>::value_type>::value,
+      basic_fbstring<E, T, A, Storage>&>::type
   operator=(TP c);
 
   basic_fbstring& operator=(std::initializer_list<value_type> il) {
@@ -2879,7 +2889,7 @@ FOLLY_FBSTRING_HASH
 
 #endif // _LIBSTDCXX_FBSTRING
 
-#pragma GCC diagnostic pop
+FOLLY_POP_WARNING
 
 #undef FBSTRING_DISABLE_SSO
 #undef FBSTRING_SANITIZE_ADDRESS