middle-end/101478 - ICE with degenerate address during gimplification

When we gimplify &MEM[0B + 4] we are re-folding the address in case
types are not canonical which ends up with a constant address that
recompute_tree_invariant_for_addr_expr ICEs on.  Properly guard
that call.

	PR middle-end/101478
	* gimplify.cc (gimplify_addr_expr): Check we still have an
	ADDR_EXPR before calling recompute_tree_invariant_for_addr_expr.

	* gcc.dg/pr101478.c: New testcase.

(cherry picked from commit 33ead6400ad59d4b38fa0527a9a7b53a28114ab7)

diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index 55bc7f8624edf3092cef1414023b8a2433be1702..a7b5a3883373e99d18b219672e81517f955cf166 100644 (file)
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -6518,7 +6518,8 @@ gimplify_addr_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p)
        *expr_p = build_fold_addr_expr (op0);
 
       /* Make sure TREE_CONSTANT and TREE_SIDE_EFFECTS are set properly.  */
-      recompute_tree_invariant_for_addr_expr (*expr_p);
+      if (TREE_CODE (*expr_p) == ADDR_EXPR)
+       recompute_tree_invariant_for_addr_expr (*expr_p);
 
       /* If we re-built the ADDR_EXPR add a conversion to the original type
          if required.  */

diff --git a/gcc/testsuite/gcc.dg/pr101478.c b/gcc/testsuite/gcc.dg/pr101478.c
new file mode 100644 (file)
index 0000000..527620e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr101478.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+struct obj {
+  int n;
+  int l;
+};
+int main()
+{
+  (struct obj *)((char *)(__SIZE_TYPE__)({ 0; }) - (char *)&((struct obj *)0)->l);
+}