Fortran: NULL pointer dereference in invalid simplification [PR106985]

gcc/fortran/ChangeLog:

	PR fortran/106985
	* expr.cc (gfc_simplify_expr): Avoid NULL pointer dereference.

gcc/testsuite/ChangeLog:

	PR fortran/106985
	* gfortran.dg/pr106985.f90: New test.

(cherry picked from commit 8dbb15bc2d019488240c1e69d93121b0347ac092)

diff --git a/gcc/fortran/expr.cc b/gcc/fortran/expr.cc
index be94c18c836611289ef3a102f7ffec1e4d64c468..290ddf360c8d8615bc22832b23a5d863cea2b1a8 100644 (file)
--- a/gcc/fortran/expr.cc
+++ b/gcc/fortran/expr.cc
@@ -2287,7 +2287,8 @@ gfc_simplify_expr (gfc_expr *p, int type)
         initialization expression, or we want a subsection.  */
       if (p->symtree->n.sym->attr.flavor == FL_PARAMETER
          && (gfc_init_expr_flag || p->ref
-             || p->symtree->n.sym->value->expr_type != EXPR_ARRAY))
+             || (p->symtree->n.sym->value
+                 && p->symtree->n.sym->value->expr_type != EXPR_ARRAY)))
        {
          if (!simplify_parameter_variable (p, type))
            return false;

diff --git a/gcc/testsuite/gfortran.dg/pr106985.f90 b/gcc/testsuite/gfortran.dg/pr106985.f90
new file mode 100644 (file)
index 0000000..f4ed925
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr106985.f90
@@ -0,0 +1,8 @@
+! { dg-do compile }
+! PR fortran/106985 - ICE in gfc_simplify_expr
+! Contributed by G.Steinmetz
+
+program p
+  integer, parameter :: a(2) = 1
+  integer, parameter :: b = a(2) + b ! { dg-error "before its definition is complete" }
+end