[clang] [llvm] [AIX][TLS] Disallow the use of -maix-small-local-exec-tls and -fno-data-sections (PR #79252)

[Amy Kwan via llvm-commits]

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@@ -12,6 +15,10 @@ entry:
 ; Check that the aix-small-local-exec-tls attribute is not supported on Linux and AIX (32-bit).
 ; CHECK-NOT-SUPPORTED: The aix-small-local-exec-tls attribute is only supported on AIX in 64-bit mode.
 
+; Check that the aix-small-local-exec-tls attribute is only supported when
+; data sections are enabled.
+; CHECK-UNSUPPORTED-NO-DATASEC: The aix-small-local-exec-tls attribute can only be specified with -data-sections.
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amy-kwan wrote:

I kept the llvm portion as `-data-sections` since the option for llc is `-data-sections` rather than `-fdata-sections` (which is the option for clang).

https://github.com/llvm/llvm-project/pull/79252