[clang] [Clang] Enable -fextend-lifetimes at -Og (PR #118026)

[Jeremy Morse via cfe-commits]

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@@ -1834,6 +1834,14 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
     Opts.setInlining(CodeGenOptions::NormalInlining);
   }
 
+  // If we have specified -Og and have not set any explicit -fextend-lifetimes
+  // value, then default to -fextend-lifetimes=all.
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jmorse wrote:

This is going to create confusion by speculating the existence of an `={all,params,this}`  fextend-lifetimes when it doesn't exist yet, and might not.

https://github.com/llvm/llvm-project/pull/118026