[llvm] [LLVM][Cygwin] Enable conditions that are shared with MinGW (PR #149638)

[Martin Storsjö via llvm-commits]

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@@ -2062,7 +2062,7 @@ void TargetLoweringBase::insertSSPDeclarations(Module &M) const {
 
     // FreeBSD has "__stack_chk_guard" defined externally on libc.so
     if (M.getDirectAccessExternalData() &&
-        !TM.getTargetTriple().isWindowsGNUEnvironment() &&
+        !TM.getTargetTriple().isOSCygMing() &&
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mstorsjo wrote:

I think there could be an easily accessible test that covers this condition, which could be extended to cover cygwin too. (Remove the mingw case and run `check-llvm` to locate the existing test.)

https://github.com/llvm/llvm-project/pull/149638