Replace APFloatBase static fltSemantics data members with getter functions

At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 106170f..752f419 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -1365,7 +1365,7 @@
   }
   case APValue::Float: {
     const llvm::APFloat &Init = Value.getFloat();
-    if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf &&
+    if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf() &&
         !Context.getLangOpts().NativeHalfType &&
         !Context.getLangOpts().HalfArgsAndReturns)
       return llvm::ConstantInt::get(VMContext, Init.bitcastToAPInt());