[clang] [clang][Driver] Add flag for setting SkipFunctionBodies (PR #100135)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,13 @@
+// Trivial check to ensure skip-function-bodies flag is propagated.
+//
+// RUN: %clang_cc1 -verify -skip-function-bodies -pedantic-errors %s
+// expected-no-diagnostics
+
+int f() {
+  // normally this should emit some diags, but we're skipping it!
+  this is garbage;
+}
+
+// Make sure we only accept it as a cc1 arg.
+// RUN: not %clang -skip-function-bodies %s 2>&1 | FileCheck %s
+// CHECK: clang: error: unknown argument '-skip-function-bodies'; did you mean '-Xclang -skip-function-bodies'?
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AaronBallman wrote:

Yay for a diagnostic, *boo* for it suggesting `-Xclang` in this instance, but I think we can live with it.

https://github.com/llvm/llvm-project/pull/100135