Compilation warnings

[nigelhorne]

gpdf.c: In function ‘draw_pdf’:
gpdf.c:1348:19: warning: ‘%d’ directive writing between 1 and 10 bytes into a region of size between 4 and 13 [-Wformat-overflow=]
1348 | sprintf(s, "%d, %d", j, i);
| ^~
gpdf.c:1348:14: note: directive argument in the range [0, 2147483647]
1348 | sprintf(s, "%d, %d", j, i);
| ^~~~~~~~
gpdf.c:1348:3: note: ‘sprintf’ output between 5 and 23 bytes into a destination of size 16
1348 | sprintf(s, "%d, %d", j, i);

[billthefarmer]

I wrote this in 2016 and haven't touched it since. Gcc has obviously become more pernickety since. That particular line is outputting dimensions in points on a piece of paper which can't be bigger than A0 because, AFAIK, you can't get printers/plotters bigger than that. So it won't overflow the buffer char s[16];. You could make it bigger to make the warning go away or suppress the warning.