re PR fortran/42481 (generic interface not recognized)

2010-01-14  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/42481
	* module.c (load_generic_interfaces): If a procedure that is
	use associated but not generic is given an interface that
	includes itself, then make it generic.

2010-01-14  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/42481
	* gfortran.dg/generic_19.f90 : New test.

From-SVN: r155876

4 files changed, 78 insertions, 3 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 09bfccf..be65b9a 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,10 @@
+2010-01-14  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/42481
+	* module.c (load_generic_interfaces): If a procedure that is
+	use associated but not generic is given an interface that
+	includes itself, then make it generic.
+
 2010-01-11  Joseph Myers  <joseph@codesourcery.com>  
 	    Shujing Zhao  <pearly.zhao@oracle.com>
 
diff --git a/gcc/fortran/module.c b/gcc/fortran/module.c
index 140f2e2..667bab8 100644
--- a/gcc/fortran/module.c
+++ b/gcc/fortran/module.c
@@ -1,6 +1,7 @@
 /* Handle modules, which amounts to loading and saving symbols and
    their attendant structures.
-   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
+   2009, 2010
    Free Software Foundation, Inc.
    Contributed by Andy Vaught
 
@@ -3750,8 +3751,9 @@ load_generic_interfaces (void)
   const char *p;
   char name[GFC_MAX_SYMBOL_LEN + 1], module[GFC_MAX_SYMBOL_LEN + 1];
   gfc_symbol *sym;
-  gfc_interface *generic = NULL;
+  gfc_interface *generic = NULL, *gen = NULL;
   int n, i, renamed;
+  bool ambiguous_set = false;
 
   mio_lparen ();
 
@@ -3836,9 +3838,13 @@ load_generic_interfaces (void)
 	      sym = st->n.sym;
 
 	      if (st && !sym->attr.generic
+		     && !st->ambiguous
 		     && sym->module
 		     && strcmp(module, sym->module))
-		st->ambiguous = 1;
+		{
+		  ambiguous_set = true;
+		  st->ambiguous = 1;
+		}
 	    }
 
 	  sym->attr.use_only = only_flag;
@@ -3854,6 +3860,26 @@ load_generic_interfaces (void)
 	      sym->generic = generic;
 	      sym->attr.generic_copy = 1;
 	    }
+
+	  /* If a procedure that is not generic has generic interfaces
+	     that include itself, it is generic! We need to take care
+	     to retain symbols ambiguous that were already so.  */
+	  if (sym->attr.use_assoc
+		&& !sym->attr.generic
+		&& sym->attr.flavor == FL_PROCEDURE)
+	    {
+	      for (gen = generic; gen; gen = gen->next)
+		{
+		  if (gen->sym == sym)
+		    {
+		      sym->attr.generic = 1;
+		      if (ambiguous_set)
+		        st->ambiguous = 0;
+		      break;
+		    }
+		}
+	    }
+
 	}
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6484dd8..2195d2e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-01-14  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/42481
+	* gfortran.dg/generic_19.f90 : New test.
+
 2010-01-13  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/42730
diff --git a/gcc/testsuite/gfortran.dg/generic_19.f90 b/gcc/testsuite/gfortran.dg/generic_19.f90
new file mode 100644
index 0000000..f023c5e
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/generic_19.f90
@@ -0,0 +1,37 @@
+! { dg-do compile }
+! Test the fix for PR42481, in which 'sub' was not recognised as
+! a generic interface.
+!
+! Contributed by William Mitchell < william.mitchell@nist.gov>
+!
+module mod1
+contains
+  subroutine sub(x, chr)
+    real x
+    character(8) chr
+    if (trim (chr) .ne. "real") call abort
+    if (int (x) .ne. 1) call abort
+  end subroutine sub
+end module mod1
+
+module mod2
+  use mod1
+  interface sub
+    module procedure sub, sub_int
+  end interface sub
+contains
+  subroutine sub_int(i, chr)
+    character(8) chr
+    integer i
+    if (trim (chr) .ne. "integer") call abort
+    if (i .ne. 1) call abort
+  end subroutine sub_int
+end module mod2
+
+program prog
+  use mod1
+  use mod2
+  call sub(1, "integer ")
+  call sub(1.0, "real    ")
+end program prog
+! { dg-final { cleanup-modules "mod1 mod2" } }