[clang] [clang][PowerPC] Add flag to enable compatibility with GNU for complex arguments (PR #77732)

[zhijian lin via cfe-commits]

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@@ -0,0 +1,15 @@
+// RUN: not %clang %s --target=x86_64 -fcomplex-ppc-gnu-abi 2>&1 \
+// RUN:     | FileCheck %s -check-prefix=X86_64
+// X86_64: error: unsupported option '-fcomplex-ppc-gnu-abi' for target 'x86_64'
+
+// RUN: not %clang %s --target=ppc64 -fcomplex-ppc-gnu-abi 2>&1 \
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diggerlin wrote:

I think two test scenarios is enough , 

`if (!TC.getTriple().isPPC32() || !TC.getTriple().isOSBinFormatELF()) {`

one for `!TC.getTriple().isPPC32()` , other for `!TC.getTriple().isOSBinFormatELF()`

https://github.com/llvm/llvm-project/pull/77732