diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index cba3de897de..9dcead3472e 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,12 @@
+2007-01-17  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/30476
+	* module.c (load_generic_interfaces): Make the marking of the
+	symbol as ambiguous conditional on the module names being
+	different.
+	(write_generic): Ensure that the generic interface has a
+	non-NULL module field.
+
 2007-01-16  Roger Sayle  <roger@eyesopen.com>
 
 	PR fortran/30404
diff --git a/gcc/fortran/module.c b/gcc/fortran/module.c
index 05056a5cb44..1613a740046 100644
--- a/gcc/fortran/module.c
+++ b/gcc/fortran/module.c
@@ -3097,9 +3097,11 @@ load_generic_interfaces (void)
 	      gfc_symtree *st;
 	      p = p ? p : name;
 	      st = gfc_find_symtree (gfc_current_ns->sym_root, p);
-	      st->ambiguous = sym->attr.generic ? 0 : 1;
+	      if (!sym->attr.generic
+		    && sym->module != NULL
+		    && strcmp(module, sym->module) != 0)
+		st->ambiguous = 1;
 	    }
-
 	  if (i == 1)
 	    {
 	      mio_interface_rest (&sym->generic);
@@ -3748,6 +3750,9 @@ write_generic (gfc_symbol * sym)
       || !gfc_check_access (sym->attr.access, sym->ns->default_access))
     return;
 
+  if (sym->module == NULL)
+    sym->module = gfc_get_string (module_name);
+
   mio_symbol_interface (&sym->name, &sym->module, &sym->generic);
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b8072de9a7a..e5724aee216 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2007-01-17  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/30476
+	* gfortran.dg/generic_12.f90: New test.
+
 2007-01-17  Dorit Nuzman  <dorit@il.ibm.com>
 
 	* gcc.target/i386/vectorize1.c: Add cleanup-tree-dump.
diff --git a/gcc/testsuite/gfortran.dg/generic_12.f90 b/gcc/testsuite/gfortran.dg/generic_12.f90
new file mode 100644
index 00000000000..59c3c96e3e2
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/generic_12.f90
@@ -0,0 +1,32 @@
+! { dg-do compile }
+! Test the fix for PR30476 in which the generic interface hello
+! was found incorrectly to be ambiguous.
+!
+!Contributed by Tobias Burnus <burnus@gcc.gnu.org>
+!
+SUBROUTINE hello_x(dum)
+   IMPLICIT NONE
+   INTEGER :: dum
+   WRITE(0,*) "Hello world: ", dum
+END SUBROUTINE hello_x
+
+MODULE interfaces
+IMPLICIT NONE
+INTERFACE hello
+   SUBROUTINE hello_x(dum)
+      IMPLICIT NONE
+      INTEGER :: dum
+   END SUBROUTINE hello_x
+END INTERFACE
+END MODULE interfaces
+
+MODULE global_module
+  USE interfaces
+END MODULE global_module
+
+PROGRAM main
+  USE global_module
+  IMPLICIT NONE
+  CALL hello(10)
+END PROGRAM main
+! { dg-final { cleanup-modules "interfaces global_module" } }