[Bug libgomp/69555] libgomp.c++/target-6.C fails because of undefined behaviour

[jiwang at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69555

--- Comment #8 from Jiong Wang <jiwang at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #7)
>           {
>             try
>               {
> ...
>                 D.2689 = (sizetype) D.2477;
>                 D.2690 = D.2689 + 1;
>                 D.2691 = D.2690 * 4;
>                 D.2692 = __builtin_alloca_with_align (D.2691, 32);
>                 c = D.2692;
> 
> Accessing an automatic variable from the caller inside of target region is
> wrong, it should have been made firstprivate during gimplification, which
> would allow it to work.

This testcase failed on arm-linux-gnueabihf also. What I observed is the first
parameter of __builtin_alloca_with_align is not initialized in the last tree
pass target-6.C.210t.optimized which looks like a direct result of above
gimplification bug.