[lld] [LLD][COFF] Support /DEPENDENTLOADFLAGS[:flags] (PR #71537)

[Alexandre Ganea via llvm-commits]

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@@ -265,6 +265,19 @@ void LinkerDriver::parseFunctionPadMin(llvm::opt::Arg *a) {
   }
 }
 
+// Parses /dependentloadflag option argument.
+void LinkerDriver::parseDependentLoadFlags(llvm::opt::Arg *a) {
+  StringRef arg = a->getNumValues() ? a->getValue() : "";
+  if (!arg.empty()) {
+    if (arg.getAsInteger(0, ctx.config.dependentLoadFlags))
+      error("/dependentloadflag: invalid argument: " + arg);
+    return;
+  }
+  // MSVC linker reports error "no argument specified", although MSDN describes
+  // argument as optional.
+  error("no argument specified with option '/dependentloadflag'");
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aganea wrote:

I think this error can be made a bit more concise. Also other errors for other flags seem to put the flag in the front: "/dependentloadflag: no argument specified" 

https://github.com/llvm/llvm-project/pull/71537