diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index e9b88686c488..15105753ed54 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-11  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/77942
+	* simplify.c (gfc_simplify_cshift): Check for zero.
+
 2016-10-11  Fritz Reese  <fritzoreese@gmail.com>
 
 	* iresolve.c (get_radians, get_degrees): Fix sloppy commit.
@@ -5,7 +10,7 @@
 
 2016-10-11  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
 
-	* simplify.c (radians_f): Fix mpdr_mod.
+	* simplify.c (radians_f): Fix mpfr_mod.
 	* ireolce.c (get_degrees): Declare tmp.
 
 2016-10-11  Fritz Reese  <fritzoreese@gmail.com>
diff --git a/gcc/fortran/simplify.c b/gcc/fortran/simplify.c
index eb6e41258fb8..b593bce1f4a5 100644
--- a/gcc/fortran/simplify.c
+++ b/gcc/fortran/simplify.c
@@ -1989,7 +1989,7 @@ gfc_simplify_cshift (gfc_expr *array, gfc_expr *shift, gfc_expr *dim)
       shft = shft < 0 ? 1 - shft : shft;
 
       /* Special case: Shift to the original order!  */
-      if (shft % sz == 0)
+      if (sz == 0 || shft % sz == 0)
 	return a;
 
       result = gfc_copy_expr (a);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e1ed8e5250f7..1c574b9189eb 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-11  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/77942
+	* gfortran.dg/pr77942.f90
+
 2016-10-11  Fritz Reese  <fritzoreese@gmail.com>
 
 	* gfortran.dg/dec_math.f90: New testsuite.
diff --git a/gcc/testsuite/gfortran.dg/pr77942.f90 b/gcc/testsuite/gfortran.dg/pr77942.f90
new file mode 100644
index 000000000000..7d46afbd41c7
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr77942.f90
@@ -0,0 +1,5 @@
+! { dg-do compile }
+program p
+   character, parameter :: c(2) = 'a'
+   print *, cshift(c(2:1), 1)
+end