mprintf: avoid unsigned integer overflow warning

The overflow has no real world impact.
Just avoid it for "best practice".

Code change suggested by "The Infinnovation Team" and Daniel Stenberg.
Closes #3184

diff --git a/lib/mprintf.c b/lib/mprintf.c
index d2d91d7438783905bc83c2757b828cb6ce00734e..e1909367824d3cc0471219d2f2eefac5fb513d33 100644 (file)
--- a/lib/mprintf.c
+++ b/lib/mprintf.c
@@ -835,7 +835,7 @@ static int dprintf_formatf(
           while(width-- > 0)
             OUTCHAR(' ');
 
-        while((len-- > 0) && *str)
+        for(; len && *str; len--)
           OUTCHAR(*str++);
         if(p->flags&FLAGS_LEFT)
           while(width-- > 0)