From a4fbab560a202f4541f8f9a872774b2cbf72b4b0 Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Mon, 16 Jan 2023 21:41:09 +0100
Subject: [PATCH] Fortran: fix ICE in check_charlen_present [PR108420]

gcc/fortran/ChangeLog:

	PR fortran/108420
	* iresolve.cc (check_charlen_present): Preserve character length if
	there is no array constructor.

gcc/testsuite/ChangeLog:

	PR fortran/108420
	* gfortran.dg/pr108420.f90: New test.
---
 gcc/fortran/iresolve.cc                |  9 ++++++---
 gcc/testsuite/gfortran.dg/pr108420.f90 | 10 ++++++++++
 2 files changed, 16 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/gfortran.dg/pr108420.f90

diff --git a/gcc/fortran/iresolve.cc b/gcc/fortran/iresolve.cc
index 711e9178ad4..33794f0a858 100644
--- a/gcc/fortran/iresolve.cc
+++ b/gcc/fortran/iresolve.cc
@@ -94,9 +94,12 @@ check_charlen_present (gfc_expr *source)
   else if (source->expr_type == EXPR_ARRAY)
     {
       gfc_constructor *c = gfc_constructor_first (source->value.constructor);
-      source->ts.u.cl->length
-		= gfc_get_int_expr (gfc_charlen_int_kind, NULL,
-				    c->expr->value.character.length);
+      if (c)
+	source->ts.u.cl->length
+	  = gfc_get_int_expr (gfc_charlen_int_kind, NULL,
+			      c->expr->value.character.length);
+      if (source->ts.u.cl->length == NULL)
+	gfc_internal_error ("check_charlen_present(): length not set");
     }
 }

diff --git a/gcc/testsuite/gfortran.dg/pr108420.f90 b/gcc/testsuite/gfortran.dg/pr108420.f90
new file mode 100644
index 00000000000..985c0b3bf53
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr108420.f90
@@ -0,0 +1,10 @@
+! { dg-do compile }
+! PR fortran/108420
+! Contributed by G.Steinmetz
+
+program p
+  character :: c = 'c'
+  logical   :: m = .true.
+  print *, merge(transfer('a', 'b', 0), c, .true.)
+  print *, merge(transfer('a', 'b', 0), c, m)
+end
--
2.35.3