[clang] [Clang][AArch64] Expose compatible SVE intrinsics with only +sme (PR #95787)

[Sander de Smalen via cfe-commits]

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@@ -17,7 +25,7 @@
 // CPP-CHECK-NEXT:    [[TMP1:%.*]] = shl nuw nsw i64 [[TMP0]], 4
 // CPP-CHECK-NEXT:    ret i64 [[TMP1]]
 //
-uint64_t test_svcntb()
+uint64_t test_svcntb(void) MODE_ATTR
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sdesmalen-arm wrote:

I don't think so.

The ACLE describes that the SME keyword attributes cannot be used with K&R unprototyped C functions, https://github.com/ARM-software/acle/blob/main/main/acle.md#sme-keyword-attributes

Clang gives a clear diagnostic describing the issue:  https://godbolt.org/z/7GabEWro1

https://github.com/llvm/llvm-project/pull/95787