[Flang] funderscoring intermittent failure fix

[madanial]

Summary

There is an intermittent failure in the tests for the funderscoring driver option reported in (https://lab.llvm.org/buildbot/#/builders/21/builds/78228) that is caused by an uninitialized member variable.

[DavidSpickett]

I looked at that myself but for some reason thought it would default construct to false, but of course that doesn't apply to bool. Good catch!

I have no context on the option itself so I'll let the others confirm that false is the right value here.

[kkwli0]

Yes, usePassOpt should be initialized to false.

LGTM

[kkwli0]

Tracked in https://github.com/llvm/llvm-project/issues/64822

flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp

public:
 
   ExternalNameConversionPass() { usePassOpt = true; }
 
   mlir::ModuleOp getModule() { return getOperation(); }
   void runOnOperation() override;
 
 private:
   bool appendUnderscores;
-  bool usePassOpt;
+  bool usePassOpt = false;
 };
 } // namespace
 
 void ExternalNameConversionPass::runOnOperation() {
   auto op = getOperation();
   auto *context = &getContext();
 
   appendUnderscores = (usePassOpt) ? appendUnderscoreOpt : appendUnderscores;