Long introduction - but the patch is rather simple: Don't use kind=1
as type where kind=4 should be used.

Looooong introduction + background, feel free to skip.

---------------<intro/background>-------------

This popped up for libgomp/testsuite/libgomp.fortran/struct-elem-map-1.f90
which uses kind=4 characters – if Sandra's "Fortran: delinearize multi-dimensional
array accesses" patch is applied.

Patch: https://gcc.gnu.org/pipermail/gcc-patches/2020-December/562230.html
Used for OG11: https://gcc.gnu.org/pipermail/gcc-patches/2021-November/584716.html
On the OG12 alias devel/omp/gcc-12 vendor branch, it is used:
https://gcc.gnu.org/g:39a8c371fda6136cf77c74895a00b136409e0ba3

* * *

For mainline, I did not observe a wrong-code issue at runtime, still:

void frobc (character(kind=4)[1:*_a] * & restrict a, ...
...
static void frobc (character(kind=1) * & restrict, ...

feels odd, i.e. having the definition as kind=4 and the declaration as kind=1.
With the patch, it becomes:

static void frobc (character(kind=4) * & restrict, character(kind=4) * &, ...

  * * *

For the following, questionable code (→ PR107266), it is even worse:

character(kind=4) function f(x) bind(C)
   character(kind=4), value :: x
end

this gives the following, which has the wrong ABI:

character(kind=1) f (character(kind=1) x)
{
   (void) 0;
}

With the patch, it becomes:
   character(kind=4) f (character(kind=4) x)

  * * *

I think that all only exercises the trans-type.cc patch;
the trans-expr.cc code gets called – as an assert shows,
but I fail to get a dump where this goes wrong.

However, for struct-elem-map-1.f90 with mainline or with
OG12 and the patch:
   #pragma omp target map(tofrom:var.uni2[40 / 20] [len: 20])

while on OG12 without the attached patch:
   #pragma omp target map(tofrom:var.uni2[40 / 5] [len: 5])

where the problem is that TYPE_SIZE_UNIT is wrong. Whether
this only affects OG12 due to the delinearizer patch or
some code on mainline as well, I don't know.

Still, I think it should be fixed ...

---------------<END of intro/background>-------------

OK for mainline?

Tobias
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