WindowsX86: long double is x87DoubleExtended on mingw-w64

[martell]

Summary

Fixes:
https://llvm.org/bugs/show_bug.cgi?id=24398

[rnk]

lgtm

[martell]

Landed in rL245084

The commit parser is bugged :/

[martell]

Hans this is something we most definitely should have in 3.7
It's a pretty big bugfix for this target :)

[hans]

I'm OK with it if Richard gives owner's approval.

Cheers,
Hans

lib/Basic/Targets.cpp

 class MinGWX86_32TargetInfo : public WindowsX86_32TargetInfo {
 public:
   MinGWX86_32TargetInfo(const llvm::Triple &Triple)
-      : WindowsX86_32TargetInfo(Triple) {}
+      : WindowsX86_32TargetInfo(Triple) {
+    LongDoubleWidth = LongDoubleAlign = 128;
+    LongDoubleFormat = &llvm::APFloat::x87DoubleExtended;
+  }
   void getTargetDefines(const LangOptions &Opts,
                         MacroBuilder &Builder) const override {
     WindowsX86_32TargetInfo::getTargetDefines(Opts, Builder);

 class MinGWX86_64TargetInfo : public WindowsX86_64TargetInfo {
 public:
   MinGWX86_64TargetInfo(const llvm::Triple &Triple)
-      : WindowsX86_64TargetInfo(Triple) {}
+      : WindowsX86_64TargetInfo(Triple) {
+    LongDoubleWidth = LongDoubleAlign = 128;
+    LongDoubleFormat = &llvm::APFloat::x87DoubleExtended;
+  }
   void getTargetDefines(const LangOptions &Opts,
                         MacroBuilder &Builder) const override {
     WindowsX86_64TargetInfo::getTargetDefines(Opts, Builder);