From 3f0e4b23038ade2cd14d93b0705af93848ee45c2 Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Sat, 28 Jan 2023 17:59:23 +0100
Subject: [PATCH] Fortran: diagnose USE associated symbols in COMMON blocks
[PR108453]
gcc/fortran/ChangeLog:
PR fortran/108453
* match.cc (gfc_match_common): A USE associated name shall not appear
in a COMMON block (F2018:C8121).
gcc/testsuite/ChangeLog:
PR fortran/108453
* gfortran.dg/common_27.f90: New test.
---
gcc/fortran/match.cc | 10 ++++++++++
gcc/testsuite/gfortran.dg/common_27.f90 | 14 ++++++++++++++
2 files changed, 24 insertions(+)
create mode 100644 gcc/testsuite/gfortran.dg/common_27.f90
@@ -5345,6 +5345,16 @@ gfc_match_common (void)
goto cleanup;
}
+ /* F2018:R874: common-block-object is variable-name [ (array-spec) ]
+ F2018:C8121: A variable-name shall not be a name made accessible
+ by use association. */
+ if (sym->attr.use_assoc)
+ {
+ gfc_error ("Symbol %qs at %C is USE associated from module %qs "
+ "and cannot occur in COMMON", sym->name, sym->module);
+ goto cleanup;
+ }
+
/* Deal with an optional array specification after the
symbol name. */
m = gfc_match_array_spec (&as, true, true);
new file mode 100644
@@ -0,0 +1,14 @@
+! { dg-do compile }
+! PR fortran/108453 - a use associated variable cannot occur in COMMON
+! Contributed by G.Steinmetz
+
+module m
+ type t
+ end type
+ real :: r
+end
+program p
+ use m, only: t, r
+ common t ! { dg-error "USE associated from module" }
+ common /cm/ r ! { dg-error "USE associated from module" }
+end
--
2.35.3