No need to run buildO0defaultPipeline manually.

ptersilie · ptersilie · commit a5d59b7de9bd · 2023-11-03T13:58:28.000Z
The call to `PB.parsePassPipeline` will make sure the default pipeline is run.
This is now equivalent to how custom pipelines are ran in `LTOBackend`.
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1027,7 +1027,6 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
     }
 
     if (!NewPMPasses.empty()) {
-      MPM.addPass(PB.buildO0DefaultPipeline(Level, PrepareForThinLTO || PrepareForLTO));
       if (auto Err = PB.parsePassPipeline(MPM, NewPMPasses)) {
         report_fatal_error(Twine("unable to parse pass pipeline description '") +
             NewPMPasses + "': " + toString(std::move(Err)));

Original file line number	Diff line number	Diff line change
`@@ -1027,7 +1027,6 @@ void EmitAssemblyHelper::RunOptimizationPipeline(`
`1027`	`1027`	`}`
`1028`	`1028`
`1029`	`1029`	`if (!NewPMPasses.empty()) {`
`1030`		`- MPM.addPass(PB.buildO0DefaultPipeline(Level, PrepareForThinLTO \|\| PrepareForLTO));`
`1031`	`1030`	`if (auto Err = PB.parsePassPipeline(MPM, NewPMPasses)) {`
`1032`	`1031`	`report_fatal_error(Twine("unable to parse pass pipeline description '") +`
`1033`	`1032`	`NewPMPasses + "': " + toString(std::move(Err)));`