Purify is reporting an overlapping copy. For example, line 91 of the _fptostr routine, one of Microsoft's workhorse floating point conversion routines, contains the following call to strcpy:
87 else{
88 /* move the entire string to the left one digit to remove the
89 * unused overflow digit.
90 */
91 strcpy(buf,buf+1);
92 }
Microsoft documentation for strcpy() says "the behavior of strcpy is undefined if the source and destination strings overlap".
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