[Bug fortran/126386] matmul in combination with multiplication and transpose fails to correctly reallocate result array

"cvs-commit at gcc dot gnu.org via Gcc-bugs" <[email protected]> Mon, 27 Jul 2026 18:30:09 +0000

Newsgroups	gmane.comp.gcc.bugs
Message-ID	<[email protected]/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126386

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-16 branch has been updated by Thomas Koenig
<[email protected]>:

https://gcc.gnu.org/g:72e30ac4747bcd51c20fc866036ed5e49a2ff5cc

commit r16-9418-g72e30ac4747bcd51c20fc866036ed5e49a2ff5cc
Author: Thomas Koenig <[email protected]>
Date:   Sun Jul 26 13:41:32 2026 +0200

    Fix size calculation for reallocation for matmul of rank 2 a and rank 1 b.

    This is a rather simple one-character (well, two-bit) fix for th
    calculation of the size of the reallocation of the LHS if that
    is allocatable.

    gcc/fortran/ChangeLog:

            PR fortran/126386
            * frontend-passes.cc (matmul_lhs_realloc):  Fix size calculation of
            A2B1 case.

    gcc/testsuite/ChangeLog:

            PR fortran/126386
            * gfortran.dg/inline_matmul_28.f90: New test.

    (cherry picked from commit 4d855f3af5b18e539585d1d4832470e500323c12)