From c12facd22881517127ebbe213d7ecc7fc1fcea4e Mon Sep 17 00:00:00 2001 From: Tobias Burnus Date: Thu, 17 Sep 2020 14:01:09 +0200 Subject: [PATCH] Fortran: Avoid double-free with parse error (PR96041, PR93423) gcc/fortran/ PR fortran/96041 PR fortran/93423 * decl.c (gfc_match_submod_proc): Avoid later double-free in the error case. --- gcc/fortran/decl.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c index c612b492f3e..326e6f5db7a 100644 --- a/gcc/fortran/decl.c +++ b/gcc/fortran/decl.c @@ -9819,6 +9819,15 @@ gfc_match_submod_proc (void) if (gfc_match_eos () != MATCH_YES) { + /* Unset st->n.sym. Note: in reject_statement (), the symbol changes are + undone, such that the st->n.sym->formal points to the original symbol; + if now this namespace is finalized, the formal namespace is freed, + but it might be still needed in the parent namespace. */ + gfc_symtree *st = gfc_find_symtree (gfc_current_ns->sym_root, sym->name); + st->n.sym = NULL; + gfc_free_symbol (sym->tlink); + sym->tlink = NULL; + sym->refs--; gfc_syntax_error (ST_MODULE_PROC); return MATCH_ERROR; } -- 2.30.2