[Bug c/67661] Wrong warning when declare VLAs: operation on 'x' may be undefined [-Wsequence-point]

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67661

--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
You'll need to give a full testcase (complete compilable file and options 
used to compile it).  What you gave isn't a compilable testcase; it gives 
"error: variably modified 'y' at file scope".  Put inside a function, it 
gives "warning: unused variable 'y' [-Wunused-variable]", but does not 
give the warning you mention.  And there's no variable 'b' in your example 
at all.