Finding variable-length arrays in code

Question

When the size of my input is big enough, segmentation fault sprouts where variable-length arrays are used in a project. I want to remove them all, how to make GCC display every declaration it finds of a variable-length array?

I have tried using -Wstack-usage=1000 and filtering for the message warning: stack usage might be unbounded, but that gives me the function, not the declaration. Is there a better way?

use option `-std=c89 -pedantic` then `warning: ISO C90 forbids variable length array` — BLUEPIXY, Mar 15 '16 at 14:05
Removing all VLAs sound like overkill. You just need to remove oversized or VLAs with unpredictable size. Maybe you can grep them. — too honest for this site, Mar 15 '16 at 14:07
Well, I don't really consider a VLA where the size is a `static const` variable... — lvella, Mar 15 '16 at 14:08
I'm mildly alarmed just *how* terrible the code has to be if knowing the function that contains the VLA is not enough. — EOF, Mar 15 '16 at 21:15

score 8 · Accepted Answer · answered Mar 15 '16 at 14:13

8

I was pretty sure I have done that before, and thanks to the comments I found the solution again: use -Wvla compiler switch.

answered Mar 15 '16 at 14:13

lvella

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Finding variable-length arrays in code

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