[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:

This bit looks to be somewhat disjoint from the rest of the change here (also for what's outlined in the commit message).

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