re PR fortran/88269 (ICE in gfc_format_decoder, at fortran/error.c:947)

2018-12-10  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/88269
	* io.c (io_constraint): Update macro. If locus line buffer is NULL,
	use gfc_current_locus in error messages.
	(check_io_constraints): Catch missing IO UNIT in write and read
	statements.  io_constraint macro is incompatible here.

2018-12-10  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/88269
	* gfortran.dg/pr88269.f90: New test.

From-SVN: r266959

gcc/fortran/ChangeLog

+2018-12-10  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/88269
+	* io.c (io_constraint): Update macro. If locus line buffer is NULL,
+	use gfc_current_locus in error messages.
+	(check_io_constraints): Catch missing IO UNIT in write and read
+	statements.  io_constraint macro is incompatible here.
+
 2018-12-09  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	PR fortran/88205

gcc/fortran/io.c

@@ -3678,10 +3678,13 @@ static match
 check_io_constraints (io_kind k, gfc_dt *dt, gfc_code *io_code,
 		      locus *spec_end)
 {
-#define io_constraint(condition,msg,arg)\
+#define io_constraint(condition, msg, arg)\
 if (condition) \
   {\
-    gfc_error(msg,arg);\
+    if ((arg)->lb != NULL)\
+      gfc_error ((msg), (arg));\
+    else\
+      gfc_error ((msg), &gfc_current_locus);\
     m = MATCH_ERROR;\
   }
 
@@ -3741,11 +3744,14 @@ if (condition) \
   if (expr && expr->ts.type != BT_CHARACTER)
     {
 
-      io_constraint (gfc_pure (NULL) && (k == M_READ || k == M_WRITE),
-		     "IO UNIT in %s statement at %C must be "
+      if (gfc_pure (NULL) && (k == M_READ || k == M_WRITE))
+	{
+	  gfc_error ("IO UNIT in %s statement at %C must be "
 		     "an internal file in a PURE procedure",
 		     io_kind_name (k));
-
+	  return MATCH_ERROR;
+	}
+	  
       if (k == M_READ || k == M_WRITE)
 	gfc_unset_implicit_pure (NULL);
     }

gcc/testsuite/ChangeLog

+2018-12-10  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/88269
+	* gfortran.dg/pr88269.f90: New test.
+
 2018-12-10  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR target/88418

gcc/testsuite/gfortran.dg/pr88269.f90

+! { dg-do compile }
+! PR fortran/88269
+program p
+   write (end=1e1) ! { dg-error "tag not allowed" }
+end
+