[clang] [llvm] [ubsan] Change ubsan-unique-traps to use nomerge instead of counter (PR #117651)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,106 @@
+// NOTE: Assertions have mostly been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+// The most important assertion is the attributes at the end of the file, which
+// shows that ubsan attaches 'nomerge' to each ubsantrap intrinsic.
+//
+// RUN: %clang -fsanitize=signed-integer-overflow -S -emit-llvm -fsanitize-trap=all -O3 -mllvm -ubsan-unique-traps %s -o - \
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MaskRay wrote:

should use clang_cc1 and an explicit triple

https://github.com/llvm/llvm-project/pull/117651