Fix issue2588: Do not execute str[size-1] = '\0' when a 0 size is

passed in.  (The assert won't prevent this in non-debug builds).

diff --git a/Python/mysnprintf.c b/Python/mysnprintf.c
index 8c477946427d1cd70d9e4b59edfffe53761fcc54..3173863c466f6aa16b3e1f682ee46de63f152c47 100644 (file)
--- a/Python/mysnprintf.c
+++ b/Python/mysnprintf.c
@@ -98,7 +98,8 @@ PyOS_vsnprintf(char *str, size_t size, const char  *format, va_list va)
        PyMem_FREE(buffer);
 #endif
 Done:
-       str[size-1] = '\0';
+       if (size > 0)
+               str[size-1] = '\0';
        return len;
 #undef _PyOS_vsnprintf_EXTRA_SPACE
 }