[clang] [DTLTO][PS4,PS5] Suppress system headers directory warning (PR #167685)

[Ben Dunbobbin via cfe-commits]

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@@ -33,6 +36,11 @@
 /// headers and libraries.
 // RUN: env SCE_PROSPERO_SDK_DIR=.. %clang @%t.rsp %s 2>&1 | FileCheck -check-prefixes=WARN-SYS-HEADERS,WARN-SYS-LIBS,NO-WARN %s
 
+/// -fthinlto-index= warning suppression.
+// RUN: %clang -O2 %s -flto=thin -c -o %t.o
+// RUN: llvm-lto -thinlto -o %t %t.o
+// RUN: env SCE_PROSPERO_SDK_DIR=.. %clang @%t.rsp %t.o -fthinlto-index=%t.thinlto.bc 2>&1 | FileCheck -check-prefixes=NO-WARN %s
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bd1976bris wrote:

Should we add the `-c` to make this more realistic?

https://github.com/llvm/llvm-project/pull/167685