[gcc(refs/vendors/ARM/heads/arm-struct-reorg-wip)] PR fortran/95340 - ICE in gfc_match_select_rank, at fortran/match.c:6690

[Tamar Christina]

https://gcc.gnu.org/g:687147abdfccc1b53adc9a2d31e419719f3deaab

commit 687147abdfccc1b53adc9a2d31e419719f3deaab
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Sun Jun 28 16:24:15 2020 +0200

    PR fortran/95340 - ICE in gfc_match_select_rank, at fortran/match.c:6690
    
    Do not dereference NULL pointer when querying array shape of possibly
    improperly delared variable.
    
    gcc/fortran/
            PR fortran/95340
            * match.c (gfc_match_select_rank): Do not dereference NULL pointer.
    
    (cherry picked from commit b62cac6d92ff251213753475b69ec0b269cb7fae)

Diff:
---
 gcc/fortran/match.c                   |  3 ++-
 gcc/testsuite/gfortran.dg/pr95340.f90 | 10 ++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index b011634792e..db5174f3f21 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -6695,7 +6695,8 @@ gfc_match_select_rank (void)
       if (expr1->symtree)
 	{
 	  sym = expr1->symtree->n.sym;
-	  as = sym->ts.type == BT_CLASS ? CLASS_DATA (sym)->as : sym->as;
+	  as = (sym->ts.type == BT_CLASS
+		&& CLASS_DATA (sym)) ? CLASS_DATA (sym)->as : sym->as;
 	}
 
       if (expr1->expr_type != EXPR_VARIABLE
diff --git a/gcc/testsuite/gfortran.dg/pr95340.f90 b/gcc/testsuite/gfortran.dg/pr95340.f90
new file mode 100644
index 00000000000..edcdc935057
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr95340.f90
@@ -0,0 +1,10 @@
+! { dg-do compile }
+! PR fortran/95340 - ICE in gfc_match_select_rank, at fortran/match.c:6690
+
+program p
+  type t
+  end type t
+  class(t) :: z   ! { dg-error "must be dummy, allocatable or pointer" }
+  select rank (z) ! { dg-error "must be an assumed rank variable" }
+  end select      ! { dg-error "Expecting END PROGRAM" }
+end