From ece8b0fce6bbfb1e531de8164da47eeed80d3cf1 Mon Sep 17 00:00:00 2001
From: Tobias Burnus <tobias@codesourcery.com>
Date: Wed, 6 Oct 2021 08:47:40 +0200
Subject: [PATCH] Fortran: Fix deprecate warning with parameter

Only warn with !GCC$ ATTRIBUTES DEPRECATED if
deprecated PARMETERS are actually used.

gcc/fortran/ChangeLog:

	* resolve.c (resolve_values): Only show
	deprecated warning if attr.referenced.

gcc/testsuite/ChangeLog:

	* gfortran.dg/attr_deprecated-2.f90: New test.
---
 gcc/fortran/resolve.c                         |  2 +-
 .../gfortran.dg/attr_deprecated-2.f90         | 22 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gfortran.dg/attr_deprecated-2.f90

diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index 511fe3a5e55..0d0af39d23f 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -12351,7 +12351,7 @@ resolve_values (gfc_symbol *sym)
   if (sym->value == NULL)
     return;
 
-  if (sym->attr.ext_attr & (1 << EXT_ATTR_DEPRECATED))
+  if (sym->attr.ext_attr & (1 << EXT_ATTR_DEPRECATED) && sym->attr.referenced)
     gfc_warning (OPT_Wdeprecated_declarations,
 		 "Using parameter %qs declared at %L is deprecated",
 		 sym->name, &sym->declared_at);
diff --git a/gcc/testsuite/gfortran.dg/attr_deprecated-2.f90 b/gcc/testsuite/gfortran.dg/attr_deprecated-2.f90
new file mode 100644
index 00000000000..97a365a7c4a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/attr_deprecated-2.f90
@@ -0,0 +1,22 @@
+! { dg-do compile }
+! { dg-additional-options "-Wall" }
+!
+! Ensure that only those parameters are warned for which are actually used
+!
+module m
+  implicit none
+  integer, parameter :: parm = 4   ! unused
+  integer, parameter :: parm2 = 4  ! used in the main program
+  integer, parameter :: parm3 = 4  ! used in "f()" - { dg-warning "Using parameter 'parm3' declared at .1. is deprecated" }
+  integer, save :: var, var2
+!GCC$ ATTRIBUTES DEPRECATED :: parm, parm2, parm3, var, var2
+contains
+  subroutine f()
+    print *, parm3 ! warning shown above
+  end
+end module m
+
+use m  ! { dg-warning "Using parameter 'parm2' declared at .1. is deprecated" }
+implicit none
+print *, var2, parm2  ! { dg-warning "Using variable 'var2' at .1. is deprecated" }
+end