re PR fortran/17229 (parser confused by arithmetic if inside an if)

	PR fortran/17229

	* match.c (gfc_match_arithmetic_if): New function to match an
	arithmetic IF statement.
	(gfc_match_if): Use gfc_match_arithmetic_if to match an
	arithmetic IF statement embedded in a simple IF statement.

	* gfortran.dg/pr17229.f: New test.

From-SVN: r97825

1 files changed, 34 insertions, 0 deletions

diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index f433db5..f2b5311 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -899,6 +899,39 @@ cleanup:
 }
 
 
+/* We try to match an easy arithmetic IF statement. This only happens
+ * when just after having encountered a simple IF statement. This code
+ * is really duplicate with parts of the gfc_match_if code, but this is
+ * *much* easier.  */
+match
+gfc_match_arithmetic_if (void)
+{
+  gfc_st_label *l1, *l2, *l3;
+  gfc_expr *expr;
+  match m;
+
+  m = gfc_match (" ( %e ) %l , %l , %l%t", &expr, &l1, &l2, &l3);
+  if (m != MATCH_YES)
+    return m;
+
+  if (gfc_reference_st_label (l1, ST_LABEL_TARGET) == FAILURE
+      || gfc_reference_st_label (l2, ST_LABEL_TARGET) == FAILURE
+      || gfc_reference_st_label (l3, ST_LABEL_TARGET) == FAILURE)
+    {
+      gfc_free_expr (expr);
+      return MATCH_ERROR;
+    }
+
+  new_st.op = EXEC_ARITHMETIC_IF;
+  new_st.expr = expr;
+  new_st.label = l1;
+  new_st.label2 = l2;
+  new_st.label3 = l3;
+
+  return MATCH_YES;
+}
+
+
 /* The IF statement is a bit of a pain.  First of all, there are three
    forms of it, the simple IF, the IF that starts a block and the
    arithmetic IF.
@@ -1036,6 +1069,7 @@ gfc_match_if (gfc_statement * if_type)
     match ("exit", gfc_match_exit, ST_EXIT)
     match ("forall", match_simple_forall, ST_FORALL)
     match ("go to", gfc_match_goto, ST_GOTO)
+    match ("if", gfc_match_arithmetic_if, ST_ARITHMETIC_IF)
     match ("inquire", gfc_match_inquire, ST_INQUIRE)
     match ("nullify", gfc_match_nullify, ST_NULLIFY)
     match ("open", gfc_match_open, ST_OPEN)