From 448c89d590455ed4ab7abc40309b5cf8ec52d13d Mon Sep 17 00:00:00 2001 From: Iain Sandoe Date: Thu, 30 Apr 2020 10:42:36 +0100 Subject: [PATCH] coroutines: Fix handling of artificial vars [PR94886] The testcase ICEs because the range-based for generates three artificial variables that need to be allocated to the coroutine frame but, when walking the BIND_EXR that contains these, the DECL_INITIAL for one of them refers to an entry appearing later, which means that the frame entry hasn't been allocated when that INITIAL is walked. The solution is to defer walking the DECL_INITIAL/SIZE etc. until all the BIND_EXPR vars have been processed. gcc/cp/ChangeLog: 2020-04-30 Iain Sandoe PR c++/94886 * coroutines.cc (transform_local_var_uses): Defer walking the DECL_INITIALs of BIND_EXPR vars until all the frame allocations have been made. gcc/testsuite/ChangeLog: 2020-04-30 Iain Sandoe PR c++/94886 * g++.dg/coroutines/pr94886-folly-3.C: New test. --- gcc/cp/ChangeLog | 7 ++++++ gcc/cp/coroutines.cc | 24 ++++++++++++------- gcc/testsuite/ChangeLog | 5 ++++ .../g++.dg/coroutines/pr94886-folly-3.C | 15 ++++++++++++ 4 files changed, 43 insertions(+), 8 deletions(-) create mode 100644 gcc/testsuite/g++.dg/coroutines/pr94886-folly-3.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 62f997eb4592..1fa0e123cb11 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,10 @@ +2020-04-30 Iain Sandoe + + PR c++/94886 + * coroutines.cc (transform_local_var_uses): Defer walking + the DECL_INITIALs of BIND_EXPR vars until all the frame + allocations have been made. + 2020-04-30 Iain Sandoe PR c++/94883 diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc index cb9074e4c170..e90d3d5a3b39 100644 --- a/gcc/cp/coroutines.cc +++ b/gcc/cp/coroutines.cc @@ -1814,14 +1814,6 @@ transform_local_var_uses (tree *stmt, int *do_subtree, void *d) /* Re-write the variable's context to be in the actor func. */ DECL_CONTEXT (lvar) = lvd->context; - /* we need to walk some of the decl trees, which might contain - references to vars replaced at a higher level. */ - cp_walk_tree (&DECL_INITIAL (lvar), transform_local_var_uses, d, - NULL); - cp_walk_tree (&DECL_SIZE (lvar), transform_local_var_uses, d, NULL); - cp_walk_tree (&DECL_SIZE_UNIT (lvar), transform_local_var_uses, d, - NULL); - /* For capture proxies, this could include the decl value expr. */ if (local_var.is_lambda_capture || local_var.has_value_expr_p) { @@ -1843,6 +1835,22 @@ transform_local_var_uses (tree *stmt, int *do_subtree, void *d) lvd->actor_frame, fld_ref, NULL_TREE); local_var.field_idx = fld_idx; } + /* FIXME: we should be able to do this in the loop above, but (at least + for range for) there are cases where the DECL_INITIAL contains + forward references. + So, now we've built the revised var in the frame, substitute uses of + it in initializers and the bind expr body. */ + for (lvar = BIND_EXPR_VARS (*stmt); lvar != NULL; + lvar = DECL_CHAIN (lvar)) + { + /* we need to walk some of the decl trees, which might contain + references to vars replaced at a higher level. */ + cp_walk_tree (&DECL_INITIAL (lvar), transform_local_var_uses, d, + NULL); + cp_walk_tree (&DECL_SIZE (lvar), transform_local_var_uses, d, NULL); + cp_walk_tree (&DECL_SIZE_UNIT (lvar), transform_local_var_uses, d, + NULL); + } cp_walk_tree (&BIND_EXPR_BODY (*stmt), transform_local_var_uses, d, NULL); /* Now we have processed and removed references to the original vars, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 369ce423fbcf..7d5ae7533400 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2020-04-30 Iain Sandoe + + PR c++/94886 + * g++.dg/coroutines/pr94886-folly-3.C: New test. + 2020-04-30 Iain Sandoe PR c++/94883 diff --git a/gcc/testsuite/g++.dg/coroutines/pr94886-folly-3.C b/gcc/testsuite/g++.dg/coroutines/pr94886-folly-3.C new file mode 100644 index 000000000000..d7bd2c17d4a8 --- /dev/null +++ b/gcc/testsuite/g++.dg/coroutines/pr94886-folly-3.C @@ -0,0 +1,15 @@ + +#include "coro.h" +#include "coro1-ret-int-yield-int.h" + +#include + +coro1 +my_coro () +{ + const std::array expectedValues = {{0, 3, 1, 4, 2}}; + + for (int expectedValue : expectedValues) { + co_yield expectedValue; + } +} -- 2.47.3