[clang] Disable -gsplit-dwarf as it is unsupported at the moment on AIX (PR #158199)

[David Tenty via cfe-commits]

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@@ -0,0 +1,12 @@
+// Verify error message is emitted for `-gsplit-dwarf` on AIX 
+// as it's unsupported at the moment.
+
+// RUN: not %clang -target powerpc-ibm-aix -gdwarf-4 -gsplit-dwarf %s 2>&1 \
+// RUN: | FileCheck %s --check-prefix=UNSUP_OPT_AIX
+// RUN: not %clang -target powerpc64-ibm-aix -gdwarf-4 -gsplit-dwarf %s 2>&1 \
+// RUN: | FileCheck %s --check-prefix=UNSUP_OPT_AIX64
+
+// UNSUP_OPT_AIX: error: unsupported option '-gsplit-dwarf' for target 'powerpc-ibm-aix'
+// UNSUP_OPT_AIX64: error: unsupported option '-gsplit-dwarf' for target 'powerpc64-ibm-aix'
+
+int main(){return 0;}
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daltenty wrote:

nit: missing new line at end of file

https://github.com/llvm/llvm-project/pull/158199