Hi!
The following testcase FAILs since recently when the C++ FE started calling
protected_set_expr_location more often.
With -g, it is called on a STATEMENT_LIST that contains a DEBUG_BEGIN_STMT
and CLEANUP_POINT_EXPR, and as STATEMENT_LISTs have !CAN_HAVE_LOCATION_P,
nothing is set. Without -g, it is called instead on the CLEANUP_POINT_EXPR
directly and changes its location.
The following patch recurses on the single non-DEBUG_BEGIN_STMT statement
of a STATEMENT_LIST if any to make the two behave the same.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2020-03-26 Jakub Jelinek <ja...@redhat.com>
PR debug/94323
* tree.c (protected_set_expr_location): Recurse on STATEMENT_LIST
that contains exactly one non-DEBUG_BEGIN_STMT statement.
* g++.dg/debug/pr94323.C: New test.
--- gcc/tree.c.jj 2020-03-23 19:46:45.552448327 +0100
+++ gcc/tree.c 2020-03-25 17:22:12.438904778 +0100
@@ -5146,6 +5146,33 @@ protected_set_expr_location (tree t, loc
{
if (CAN_HAVE_LOCATION_P (t))
SET_EXPR_LOCATION (t, loc);
+ else if (t && TREE_CODE (t) == STATEMENT_LIST)
+ {
+ /* With -gstatement-frontiers we could have a STATEMENT_LIST with
+ DEBUG_BEGIN_STMT(s) and only a single other stmt, which with
+ -g wouldn't be present and we'd have that single other stmt
+ directly instead. */
+ struct tree_statement_list_node *n = STATEMENT_LIST_HEAD (t);
+ if (!n)
+ return;
+ while (TREE_CODE (n->stmt) == DEBUG_BEGIN_STMT)
+ {
+ n = n->next;
+ if (!n)
+ return;
+ }
+ tree t2 = n->stmt;
+ do
+ {
+ n = n->next;
+ if (!n)
+ {
+ protected_set_expr_location (t2, loc);
+ return;
+ }
+ }
+ while (TREE_CODE (n->stmt) == DEBUG_BEGIN_STMT);
+ }
}
/* Data used when collecting DECLs and TYPEs for language data removal. */
--- gcc/testsuite/g++.dg/debug/pr94323.C.jj 2020-03-25 17:17:49.857819078
+0100
+++ gcc/testsuite/g++.dg/debug/pr94323.C 2020-03-25 17:17:17.533300951
+0100
@@ -0,0 +1,13 @@
+// PR debug/94323
+// { dg-do compile }
+// { dg-options "-O2 -fcompare-debug" }
+
+volatile int a;
+
+void
+foo ()
+{
+ ({
+ a;
+ });
+}
Jakub
