Dear Fortranners,
Gerhard found a case where bounds-checking for an optional,
allocatable character dummy resulted in an ICE. We'd better
not call the presence check on a non-dummy symbol, as this
will hit an assert...
Regtested on x86_64-pc-linux-gnu.
OK for mainline? And backport to 11?
(The code in question has not been touched for nearly 10 years,
so I'm expecting this to be safe).
Thanks,
Harald
PR fortran/100656 - prevent ICE in gfc_conv_expr_present
gcc/fortran/ChangeLog:
PR fortran/100656
* trans-array.c (gfc_conv_ss_startstride): Do not call check for
presence of a dummy argument when a symbol actually refers to a
non-dummy.
gcc/testsuite/ChangeLog:
PR fortran/100656
* gfortran.dg/bounds_check_22.f90: New test.
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index 6d38ea78273..7eeef554c0f 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -4718,8 +4718,9 @@ done:
/* For optional arguments, only check bounds if the argument is
present. */
- if (expr->symtree->n.sym->attr.optional
- || expr->symtree->n.sym->attr.not_always_present)
+ if ((expr->symtree->n.sym->attr.optional
+ || expr->symtree->n.sym->attr.not_always_present)
+ && expr->symtree->n.sym->attr.dummy)
tmp = build3_v (COND_EXPR,
gfc_conv_expr_present (expr->symtree->n.sym),
tmp, build_empty_stmt (input_location));
diff --git a/gcc/testsuite/gfortran.dg/bounds_check_22.f90 b/gcc/testsuite/gfortran.dg/bounds_check_22.f90
new file mode 100644
index 000..a84e3dd4f51
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/bounds_check_22.f90
@@ -0,0 +1,12 @@
+! { dg-do compile }
+! { dg-options "-fcheck=bounds" }
+! PR fortran/100656 - ICE in gfc_conv_expr_present
+
+subroutine s(x)
+ character(:), allocatable, optional :: x(:)
+ if ( present(x) ) then
+ if ( allocated(x) ) then
+x = 'a' // x // 'e'
+ end if
+ end if
+end
