lto.c (hash_canonical_type): Drop hashing of TYPE_STRING_FLAG.

	* lto.c (hash_canonical_type): Drop hashing of TYPE_STRING_FLAG.
	* tree.c (gimple_canonical_types_compatible_p): Drop comparsion of
	TYPE_STRING_FLAG.

	* gfortran.dg/lto/bind_c-2b_0.f90: New testcase
	* gfortran.dg/lto/bind_c-2b_1.c: New testcase

From-SVN: r224252

gcc/ChangeLog

 2015-06-08  Jan Hubicka  <hubicka@ucw.cz>
 
+	* tree.c (gimple_canonical_types_compatible_p): Drop comparsion of
+	TYPE_STRING_FLAG.
+
+2015-06-08  Jan Hubicka  <hubicka@ucw.cz>
+
 	* lto-streamer-out.c (lto_output_location): Stream
 	reserved locations correctly.
 	* lto-streamer-in.c (lto_output_location): Likewise.

gcc/lto/ChangeLog

+2015-06-08  Jan Hubicka  <hubicka@ucw.cz>
+
+	* lto.c (hash_canonical_type): Drop hashing of TYPE_STRING_FLAG.
+
 2015-06-08  Andrew MacLeod  <amacleod@redhat.com>
 
 	* lto-lang.c : Adjust include files.

gcc/lto/lto.c

@@ -332,17 +332,15 @@ hash_canonical_type (tree type)
   if (TREE_CODE (type) == COMPLEX_TYPE)
     hstate.add_int (TYPE_UNSIGNED (type));
 
+  /* Fortran's C_SIGNED_CHAR is !TYPE_STRING_FLAG but needs to be
+     interoperable with "signed char".  Unless all frontends are revisited to
+     agree on these types, we must ignore the flag completely.  */
+
   /* Fortran standard define C_PTR type that is compatible with every
      C pointer.  For this reason we need to glob all pointers into one.
      Still pointers in different address spaces are not compatible.  */
   if (POINTER_TYPE_P (type))
-    {
-      hstate.add_int (TYPE_ADDR_SPACE (TREE_TYPE (type)));
-    }
-
-  /* For integer types hash only the string flag.  */
-  if (TREE_CODE (type) == INTEGER_TYPE)
-    hstate.add_int (TYPE_STRING_FLAG (type));
+    hstate.add_int (TYPE_ADDR_SPACE (TREE_TYPE (type)));
 
   /* For array types hash the domain bounds and the string flag.  */
   if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))

gcc/testsuite/gfortran.dg/lto/bind_c-2b_0.f90

+! { dg-lto-do run }
+! { dg-lto-options {{ -O3 -flto }} }
+! This testcase will abort if C_SIGNED_CHAR is not interoperable with signed
+! char
+module lto_type_merge_test
+  use, intrinsic :: iso_c_binding
+  implicit none
+
+  type, bind(c) :: MYFTYPE_1
+     integer(c_signed_char) :: chr
+     integer(c_signed_char) :: chrb
+  end type MYFTYPE_1
+
+  type(myftype_1), bind(c, name="myVar") :: myVar
+
+contains
+  subroutine types_test() bind(c)
+    myVar%chr = myVar%chrb
+  end subroutine types_test
+end module lto_type_merge_test
+

gcc/testsuite/gfortran.dg/lto/bind_c-2b_1.c

+#include <stdlib.h>
+/* interopse with myftype_1 */
+typedef struct {
+   signed char chr;
+   signed char chr2;
+} myctype_t;
+
+
+extern void abort(void);
+void types_test(void);
+/* declared in the fortran module */
+extern myctype_t myVar;
+
+int main(int argc, char **argv)
+{
+   myctype_t *cchr;
+   asm("":"=r"(cchr):"0"(&myVar));
+   cchr->chr = 1;
+   cchr->chr2 = 2;
+
+   types_test();
+
+   if(cchr->chr != 2)
+      abort();
+   if(cchr->chr2 != 2)
+      abort();
+   myVar.chr2 = 3;
+   types_test();
+
+   if(myVar.chr != 3)
+      abort();
+   if(myVar.chr2 != 3)
+      abort();
+   return 0;
+}
+

gcc/tree.c

@@ -12948,9 +12948,9 @@ gimple_canonical_types_compatible_p (const_tree t1, const_tree t2,
 	  || TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
 	return false;
 
-      if (TREE_CODE (t1) == INTEGER_TYPE
-	  && TYPE_STRING_FLAG (t1) != TYPE_STRING_FLAG (t2))
-	return false;
+      /* Fortran's C_SIGNED_CHAR is !TYPE_STRING_FLAG but needs to be
+	 interoperable with "signed char".  Unless all frontends are revisited
+	 to agree on these types, we must ignore the flag completely.  */
 
       /* Fortran standard define C_PTR type that is compatible with every
  	 C pointer.  For this reason we need to glob all pointers into one.