[libunwind] [libunwind] Remove unnecessary dependencies on fprintf and stdio.h for increased baremetal friendliness (PR #72040)

[Alexander Richardson via cfe-commits]

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@@ -681,7 +680,7 @@ inline bool LocalAddressSpace::findFunctionName(pint_t addr, char *buf,
   uint16_t nameLen;
   char *funcName = getFuncNameFromTBTable(addr, nameLen, offset);
   if (funcName != NULL) {
-    snprintf(buf, bufLen, "%.*s", nameLen, funcName);
+    strncpy(buf, funcName, nameLen < bufLen ? nameLen : bufLen);
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arichardson wrote:

This will always write up to 512 '\0' bytes. maybe best to use memcpy+strlen instead? 

https://github.com/llvm/llvm-project/pull/72040