From 3a9f6d5a8ee490adf9a18f93feaf86542642be7d Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Thu, 8 Dec 2022 22:50:45 +0100
Subject: [PATCH] Fortran: diagnose and reject duplicate CONTIGUOUS attribute
 [PR108025]

gcc/fortran/ChangeLog:

	PR fortran/108025
	* symbol.cc (gfc_add_contiguous): Diagnose and reject duplicate
	CONTIGUOUS attribute.

gcc/testsuite/ChangeLog:

	PR fortran/108025
	* gfortran.dg/contiguous_12.f90: New test.
---
 gcc/fortran/symbol.cc                       | 6 ++++++
 gcc/testsuite/gfortran.dg/contiguous_12.f90 | 7 +++++++
 2 files changed, 13 insertions(+)
 create mode 100644 gcc/testsuite/gfortran.dg/contiguous_12.f90

diff --git a/gcc/fortran/symbol.cc b/gcc/fortran/symbol.cc
index 49fb37864bd..e704e7ac2bd 100644
--- a/gcc/fortran/symbol.cc
+++ b/gcc/fortran/symbol.cc
@@ -1108,6 +1108,12 @@ gfc_add_contiguous (symbol_attribute *attr, const char *name, locus *where)
   if (check_used (attr, name, where))
     return false;

+  if (attr->contiguous)
+    {
+      duplicate_attr ("CONTIGUOUS", where);
+      return false;
+    }
+
   attr->contiguous = 1;
   return gfc_check_conflict (attr, name, where);
 }
diff --git a/gcc/testsuite/gfortran.dg/contiguous_12.f90 b/gcc/testsuite/gfortran.dg/contiguous_12.f90
new file mode 100644
index 00000000000..9c477a7a06a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/contiguous_12.f90
@@ -0,0 +1,7 @@
+! { dg-do compile }
+! PR fortran/108025
+
+subroutine foo (x)
+  real, contiguous :: x(:)
+  contiguous       :: x    ! { dg-error "Duplicate CONTIGUOUS attribute" }
+end
--
2.35.3