[llvm] [FIX] Fix undefined-behaviour in regex engine. (PR #73071)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


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``````````bash
git-clang-format --diff 42d484082cd190400e0e493a8d679762ce0efbba 54f6553107834de00401381381883561479a5e09 -- llvm/lib/Support/Regex.cpp llvm/lib/Support/regengine.inc
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/lib/Support/regengine.inc b/llvm/lib/Support/regengine.inc
index 8f5028f8bb..f9ad1e6894 100644
--- a/llvm/lib/Support/regengine.inc
+++ b/llvm/lib/Support/regengine.inc
@@ -146,8 +146,8 @@ matcher(struct re_guts *g, const char *string, size_t nmatch,
 	const char *stop;
 
 	/* simplify the situation where possible */
-        if (g->cflags&REG_NOSUB)
-		nmatch = 0;
+        if (g->cflags & REG_NOSUB)
+          nmatch = 0;
 	if (eflags&REG_STARTEND) {
 		start = string + pmatch[0].rm_so;
 		stop = string + pmatch[0].rm_eo;

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https://github.com/llvm/llvm-project/pull/73071