[llvm] [MC] AsmLexer invalid read fix. (PR #154972)

[Szymon Piotr Milczek via llvm-commits]

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@@ -0,0 +1,5 @@
+# RUN: llvm-mc -triple=x86_64 --as-lex %s
+
+# This test ensures AsmLexer doesn't perform an invalid read in a case where
+# buffer ends with '\0', ' ' or '\t'
+  
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smilczek wrote:

No line-break because last character has to be '\0', '\t' or ' '.

https://github.com/llvm/llvm-project/pull/154972