[gcc r12-860] c/100522 - avoid invalid GIMPLE in GIMPLE parsing

[Richard Biener <rguenth@gcc.gnu.org>]

https://gcc.gnu.org/g:414fe08a352eac69168f4fb3671246c84a1ac5aa

commit r12-860-g414fe08a352eac69168f4fb3671246c84a1ac5aa
Author: Richard Biener <rguenther@suse.de>
Date:   Tue May 18 08:41:43 2021 +0200

    c/100522 - avoid invalid GIMPLE in GIMPLE parsing
    
    This plugs a few easy holes avoiding ICEs down the route.
    
    2021-05-18  Richard Biener  <rguenther@suse.de>
    
            PR c/100522
    gcc/c/
            * gimple-parser.c (c_parser_gimple_postfix_expression_after_primary):
            Diagnose calls to non-functions.
            (c_parser_gimple_statement): Diagnose unexpected assignment RHS.
    
    gcc/testsuite/
            * gcc.dg/gimplefe-error-10.c: New testcase.

Diff:
---
 gcc/c/gimple-parser.c                    | 11 +++++++++++
 gcc/testsuite/gcc.dg/gimplefe-error-10.c |  8 ++++++++
 2 files changed, 19 insertions(+)

diff --git a/gcc/c/gimple-parser.c b/gcc/c/gimple-parser.c
index 398e21631d9..dfacf23c40a 100644
--- a/gcc/c/gimple-parser.c
+++ b/gcc/c/gimple-parser.c
@@ -877,6 +877,11 @@ c_parser_gimple_statement (gimple_parser &parser, gimple_seq *seq)
 	  rhs.value = build3_loc (loc, COND_EXPR, TREE_TYPE (trueval.value),
 				  rhs.value, trueval.value, falseval.value);
 	}
+      if (get_gimple_rhs_class (TREE_CODE (rhs.value)) == GIMPLE_INVALID_RHS)
+	{
+	  c_parser_error (parser, "unexpected RHS for assignment");
+	  return;
+	}
       assign = gimple_build_assign (lhs.value, rhs.value);
       gimple_seq_add_stmt_without_update (seq, assign);
       gimple_set_location (assign, loc);
@@ -1754,6 +1759,12 @@ c_parser_gimple_postfix_expression_after_primary (gimple_parser &parser,
 	      c_parser_gimple_expr_list (parser, &exprlist);
 	    c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
 				       "expected %<)%>");
+	    if (!FUNC_OR_METHOD_TYPE_P (TREE_TYPE (expr.value)))
+	      {
+		c_parser_error (parser, "invalid call to non-function");
+		expr.set_error ();
+		break;
+	      }
 	    expr.value = build_call_array_loc
 		(expr_loc, TREE_TYPE (TREE_TYPE (expr.value)),
 		 expr.value, exprlist.length (), exprlist.address ());
diff --git a/gcc/testsuite/gcc.dg/gimplefe-error-10.c b/gcc/testsuite/gcc.dg/gimplefe-error-10.c
new file mode 100644
index 00000000000..13d86ac5d1d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/gimplefe-error-10.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-options "-fgimple" } */
+
+__GIMPLE
+void foo() {
+  int t1;
+  t1_1 = t1_1(); /* { dg-error "invalid call" } */
+}