https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125860
--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Martin Jambor <[email protected]>: https://gcc.gnu.org/g:9d70d3894bda3e6529639e4ae0beb2fe14b9189e commit r17-1659-g9d70d3894bda3e6529639e4ae0beb2fe14b9189e Author: Martin Jambor <[email protected]> Date: Thu Jun 18 14:17:14 2026 +0200 fortran: Fix UBSAN error member access within null pointer (PR125860) With UBSAN instrumented compiler, compiling the testcase gfortran.dg/altreturn_5.f90 at -O3 fails with: /home/worker/buildworker/ubsan/build/gcc/fortran/interface.cc:4717:27: runtime error: member access within null pointer of type 'struct gfc_expr' This patch adds the necessary guard to avoid passing an invalid LOC to gfc_value_set_and_used even when the EXPR parameter is NULL and the function will just return. I have left the NULL-check in gfc_value_set_and_used intact so that the behavior of the function is consistent with gfc_value_used_expr (and possibly other functions). gcc/fortran/ChangeLog: 2026-06-16 Martin Jambor <[email protected]> PR fortran/125860 * interface.cc (gfc_procedure_use): Check a->expr is not NULL before calling gfc_value_set_and_used.
