PR pretty-print/67567 do not pass NULL as a string

Fortran passes NULL where a non-null string is expected by the pretty-printer,
which causes a sanitizer warning. This could have been found earlier by using
gcc_checking_assert. Even if the assertion is false, the result is just an
incomplete diagnostic, thus it seems more user-friendly to assert only when
checking. I do not have any idea how to properly fix the Fortran bug, thus this
patch simply works-around it.

gcc/fortran/ChangeLog:

2015-09-25  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	PR pretty-print/67567
	* resolve.c (resolve_fl_procedure): Work-around when iface->module
	== NULL.

gcc/ChangeLog:

2015-09-25  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	PR pretty-print/67567
	* pretty-print.c (pp_string): Add gcc_checking_assert.
	* pretty-print.h (output_buffer_append_r): Likewise.

From-SVN: r228131

gcc/ChangeLog

+2015-09-25  Manuel López-Ibáñez  <manu@gcc.gnu.org>
+
+	PR pretty-print/67567
+	* pretty-print.c (pp_string): Add gcc_checking_assert.
+	* pretty-print.h (output_buffer_append_r): Likewise.
+
 2015-09-25  Oleg Endo  <olegendo@gcc.gnu.org>
 
 	PR target/67675

gcc/fortran/ChangeLog

+2015-09-25  Manuel López-Ibáñez  <manu@gcc.gnu.org>
+
+	PR pretty-print/67567
+	* resolve.c (resolve_fl_procedure): Work-around when iface->module
+	== NULL.
+
 2015-09-21  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	* resolve.c (nonscalar_typebound_assign): Fix typos in comment.

gcc/fortran/resolve.c

@@ -11743,7 +11743,10 @@ resolve_fl_procedure (gfc_symbol *sym, int mp_flag)
 	{
 	  gfc_error ("Mismatch in PURE attribute between MODULE "
 		     "PROCEDURE at %L and its interface in %s",
-		     &sym->declared_at, iface->module);
+		     &sym->declared_at, 
+		     /* FIXME: PR fortran/67567: iface->module should
+			not be NULL !  */
+		     iface->module ? iface->module : "");
 	  return false;
 	}
 
@@ -11759,7 +11762,10 @@ resolve_fl_procedure (gfc_symbol *sym, int mp_flag)
 	{
 	  gfc_error ("Mismatch in RECURSIVE attribute between MODULE "
 		     "PROCEDURE at %L and its interface in %s",
-		     &sym->declared_at, iface->module);
+		     &sym->declared_at, 
+		     /* FIXME: PR fortran/67567: iface->module should
+			not be NULL !  */
+		     iface->module ? iface->module : "");
 	  return false;
 	}
 
@@ -11768,7 +11774,10 @@ resolve_fl_procedure (gfc_symbol *sym, int mp_flag)
 	{
 	  gfc_error ("%s between the MODULE PROCEDURE declaration "
 		     "in module %s and the declaration at %L in "
-		     "SUBMODULE %s", errmsg, iface->module,
+		     "SUBMODULE %s", errmsg, 
+		     /* FIXME: PR fortran/67567: iface->module should
+			not be NULL !  */
+		     iface->module ? iface->module : "",
 		     &sym->declared_at, sym->ns->proc_name->name);
 	  return false;
 	}

gcc/pretty-print.c

@@ -905,7 +905,8 @@ pp_character (pretty_printer *pp, int c)
 void
 pp_string (pretty_printer *pp, const char *str)
 {
-  pp_maybe_wrap_text (pp, str, str + (str ? strlen (str) : 0));
+  gcc_checking_assert (str);
+  pp_maybe_wrap_text (pp, str, str + strlen (str));
 }
 
 /* Maybe print out a whitespace if needed.  */

gcc/pretty-print.h

@@ -139,6 +139,7 @@ output_buffer_formatted_text (output_buffer *buff)
 static inline void
 output_buffer_append_r (output_buffer *buff, const char *start, int length)
 {
+  gcc_checking_assert (start);
   obstack_grow (buff->obstack, start, length);
   buff->line_length += length;
 }