From 99c791361468b61976d6054e1ec1c81fe43e6559 Mon Sep 17 00:00:00 2001
From: Jim MacArthur <jim.macarthur@codethink.co.uk>
Date: Wed, 11 Nov 2015 15:37:00 +0000
Subject: [PATCH 14/23] Allow non-logical expressions in IF statements

This feature is enabled by the `-std=extra-legacy` compiler flag.
---

    0014-Allow-non-logical-expressions-in-IF-statements.patch

diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index 682f7b0..c63b834 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -25,6 +25,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "gfortran.h"
 #include "match.h"
 #include "parse.h"
+#include "arith.h"
 
 int gfc_matching_ptr_assignment = 0;
 int gfc_matching_procptr_assignment = 0;
@@ -1666,7 +1667,17 @@ got_match:
   *p->next = new_st;
   p->next->loc = gfc_current_locus;
 
-  p->expr1 = expr;
+  if ((gfc_option.allow_std & GFC_STD_EXTRA_LEGACY)
+      && expr->ts.type != BT_LOGICAL)
+    {
+      p->expr1 = gfc_ne (expr, gfc_get_int_expr (1, &gfc_current_locus, 0), INTRINSIC_NE);
+      gfc_warning_now (0, "The type of condition in this IF statement isn't LOGICAL; it will be true if it evaluates to nonzero.");
+    }
+  else
+    {
+      p->expr1 = expr;
+    }
+  p->op = EXEC_IF;
 
   gfc_clear_new_st ();
 
diff --git a/gcc/fortran/parse.c b/gcc/fortran/parse.c
index 3aedb1d..e926ba6 100644
--- a/gcc/fortran/parse.c
+++ b/gcc/fortran/parse.c
@@ -26,6 +26,7 @@ along with GCC; see the file COPYING3.  If not see
 #include <setjmp.h>
 #include "match.h"
 #include "parse.h"
+#include "arith.h"
 
 /* Current statement label.  Zero means no statement label.  Because new_st
    can get wiped during statement matching, we have to keep it separate.  */
@@ -4036,6 +4037,14 @@ parse_if_block (void)
   d = add_statement ();
 
   d->expr1 = top->expr1;
+
+  if ((gfc_option.allow_std & GFC_STD_EXTRA_LEGACY)
+      && top->expr1->ts.type != BT_LOGICAL)
+    {
+      d->expr1 = gfc_ne (top->expr1, gfc_get_int_expr (1, &gfc_current_locus, 0), INTRINSIC_NE);
+      gfc_warning_now (0, "The type of condition in this IF statement isn't LOGICAL; it will be true if it evaluates to nonzero.");
+    }
+
   top->expr1 = NULL;
   top->block = d;