[gcc r11-8480] PR fortran/98411 - Pointless warning for static variables

[Harald Anlauf <anlauf@gcc.gnu.org>]

https://gcc.gnu.org/g:1e9e0798d2242b7908db4098136d0bfd0bc7f0e8

commit r11-8480-g1e9e0798d2242b7908db4098136d0bfd0bc7f0e8
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Mon May 17 21:35:38 2021 +0200

    PR fortran/98411 - Pointless warning for static variables
    
    Variables with explicit SAVE attribute cannot end up on the stack.
    There is no point in checking whether they should be moved off the
    stack to static storage.
    
    gcc/fortran/ChangeLog:
    
            PR fortran/98411
            * trans-decl.c (gfc_finish_var_decl): Add check for explicit SAVE
            attribute.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/98411
            * gfortran.dg/pr98411.f90: New test.
    
    (cherry picked from commit 09867aa0ef7568012650395189b735f9a34cf9b5)

Diff:
---
 gcc/fortran/trans-decl.c              |  1 +
 gcc/testsuite/gfortran.dg/pr98411.f90 | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index cc9d85543ca..7cded0a3ede 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -738,6 +738,7 @@ gfc_finish_var_decl (tree decl, gfc_symbol * sym)
   /* Keep variables larger than max-stack-var-size off stack.  */
   if (!(sym->ns->proc_name && sym->ns->proc_name->attr.recursive)
       && !sym->attr.automatic
+      && sym->attr.save != SAVE_EXPLICIT
       && INTEGER_CST_P (DECL_SIZE_UNIT (decl))
       && !gfc_can_put_var_on_stack (DECL_SIZE_UNIT (decl))
 	 /* Put variable length auto array pointers always into stack.  */
diff --git a/gcc/testsuite/gfortran.dg/pr98411.f90 b/gcc/testsuite/gfortran.dg/pr98411.f90
new file mode 100644
index 00000000000..249afaea419
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr98411.f90
@@ -0,0 +1,16 @@
+! { dg-do compile }
+! { dg-options "-Wall -fautomatic -fmax-stack-var-size=100" }
+! PR fortran/98411 - Pointless warning for static variables 
+
+module try
+  implicit none
+  integer, save :: a(1000)
+contains
+  subroutine initmodule
+    real, save :: b(1000)
+    logical    :: c(1000) ! { dg-warning "moved from stack to static storage" }
+    a(1) = 42
+    b(2) = 3.14
+    c(3) = .true.
+  end subroutine initmodule
+end module try