d: Fix ICE in gimplify_var_or_parm_decl, at gimplify.c:2755 (PR100882)

Constructor calls for temporaries were reusing the TARGET_EXPR_SLOT of a
TARGET_EXPR for an assignment, which later got passed to `build_assign',
which stripped away the outer TARGET_EXPR, leaving a reference to a lone
temporary with no declaration.

This stripping away of the TARGET_EXPR also discarded any cleanups that
may have been assigned to the expression as well.

So now the reuse of TARGET_EXPR_SLOT has been removed, and
`build_assign' now constructs assignments inside the TARGET_EXPR_INITIAL
slot.  This has also been extended to `return_expr', to deal with
possibility of a TARGET_EXPR being returned.

gcc/d/ChangeLog:

	PR d/100882
	* d-codegen.cc (build_assign): Construct initializations inside
	TARGET_EXPR_INITIAL.
	(compound_expr): Remove intermediate expressions that have no
	side-effects.
	(return_expr): Construct returns inside TARGET_EXPR_INITIAL.
	* expr.cc (ExprVisitor::visit (CallExp *)): Remove useless assignment
	to TARGET_EXPR_SLOT.

gcc/testsuite/ChangeLog:

	PR d/100882
	* gdc.dg/pr100882a.d: New test.
	* gdc.dg/pr100882b.d: New test.
	* gdc.dg/pr100882c.d: New test.
	* gdc.dg/torture/pr100882.d: New test.

1 files changed, 1 insertions, 6 deletions

diff --git a/gcc/d/expr.cc b/gcc/d/expr.cc
index aad7cbb..e76cae9 100644
--- a/gcc/d/expr.cc
+++ b/gcc/d/expr.cc
@@ -1894,15 +1894,10 @@ public:
       exp = d_convert (build_ctype (e->type), exp);
 
     /* If this call was found to be a constructor for a temporary with a
-       cleanup, then move the call inside the TARGET_EXPR.  The original
-       initializer is turned into an assignment, to keep its side effect.  */
+       cleanup, then move the call inside the TARGET_EXPR.  */
     if (cleanup != NULL_TREE)
       {
 	tree init = TARGET_EXPR_INITIAL (cleanup);
-	tree slot = TARGET_EXPR_SLOT (cleanup);
-	d_mark_addressable (slot);
-	init = build_assign (INIT_EXPR, slot, init);
-
 	TARGET_EXPR_INITIAL (cleanup) = compound_expr (init, exp);
 	exp = cleanup;
       }