[lld] [LLD][COFF] allow saving intermediate files with /lldsavetemps (PR #115131)

[Martin Storsjö via llvm-commits]

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@@ -2012,8 +2016,18 @@ void LinkerDriver::linkerMain(ArrayRef<const char *> argsArr) {
   config->ltoDebugPassManager = ltoDebugPM;
 
   // Handle /lldsavetemps
-  if (args.hasArg(OPT_lldsavetemps))
-    config->saveTemps = true;
+  if (args.hasArg(OPT_lldsavetemps)) {
+    for (const char *s : lldsaveTempsValues)
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mstorsjo wrote:

Previously, we could pass an empty `SaveTempsArgs` to `addSaveTemps` to signify that we want the default - but now we need to duplicate the set of components here. Is this an issue? (I.e. I guess the tradeoff is whether we want another bool flag, or want to wrap `llvmsaveTemps` in `std::optional`, to signify whether it is wanted but the set is empty, or whether we explicitly want to just list all the default components here.)

https://github.com/llvm/llvm-project/pull/115131