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

[Stephen Tozer via cfe-commits]

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@@ -0,0 +1,30 @@
+/// Check that we generate fake uses only when -fextend-lifetimes is set and we
+/// are not setting optnone, or when we have optimizations set to -Og and we have
+/// not passed -fno-extend-lifetimes.
+// RUN: %clang_cc1 -emit-llvm -disable-llvm-passes -O0 -fextend-lifetimes %s -o - | FileCheck %s
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SLTozer wrote:

Normally I would use implicit-check-not, but in this case we're `CHECK-NEXT`ing from the start of the function to the very end, which equally guarantees that no fake uses have been generated.

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