[clang] [-Wunsafe-buffer-usage] Warning Libc functions (PR #101583)

[Ziqing Luo via cfe-commits]

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@@ -783,6 +783,18 @@ bool ParsePrintfString(FormatStringHandler &H,
 bool ParseFormatStringHasSArg(const char *beg, const char *end,
                               const LangOptions &LO, const TargetInfo &Target);
 
+/// Parse C format string and return index (relative to `ArgIndex`) of the first
+/// found `s` specifier.  Return 0 if not found.
+/// \param I The start of the C format string; Updated to the first unparsed
+/// position upon return.
+/// \param E The end of the C format string;
+/// \param ArgIndex The argument index of the last found `s` specifier; Or the
+/// argument index of the formatter in initial case.
+unsigned ParseFormatStringFirstSArgIndex(const char *&I, const char *E,
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ziqingluo-90 wrote:

Done

https://github.com/llvm/llvm-project/pull/101583