[lld] [LLD][COFF] add __{data,bss}_{start,end}__ symbols for Cygwin support (PR #136180)

[Martin Storsjö via llvm-commits]

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@@ -2039,6 +2039,7 @@ void LinkerDriver::linkerMain(ArrayRef<const char *> argsArr) {
     parseMerge(".ctors=.rdata");
     parseMerge(".dtors=.rdata");
     parseMerge(".CRT=.rdata");
+    parseMerge(".data_cygwin_nocopy=.data");
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mstorsjo wrote:

Perhaps we could slip it in here if we just describe it in the commit message (which requires updating the PR description, for what message gets included for when its merged); ideally we'd have a test for that too, but as it's just another entry in a list, it might not be 100% necessary.

https://github.com/llvm/llvm-project/pull/136180