Hi!
Apparently the cp_free_lang_data fix wasn't sufficient, the
DECL_OMP_PRIVATIZED_MEMBER vars can be copied to child functions
but without the lang specific data so it doesn't trigger any longer,
and even trying to free it in cp_free_lang_data if it satisfies
omp_member_access_dummy_var doesn't work. So, this patch instead
looks for these variables at the end of the omp lowering phase
in methods, and removes them from GIMPLE_BIND bind vars as well as
BLOCK_VARS in the block tree.
Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk.
2018-02-10 Jakub Jelinek <ja...@redhat.com>
PR sanitizer/83987
* omp-low.c (maybe_remove_omp_member_access_dummy_vars,
remove_member_access_dummy_vars): New functions.
(lower_omp_for, lower_omp_taskreg, lower_omp_target,
lower_omp_1, execute_lower_omp): Use them.
* tree.c (cp_free_lang_data): Revert 2018-01-23 change.
* g++.dg/ubsan/pr83987-2.C: New test.
--- gcc/omp-low.c.jj 2018-01-24 17:26:25.216357997 +0100
+++ gcc/omp-low.c 2018-02-09 15:26:25.653403123 +0100
@@ -3208,6 +3208,43 @@ scan_omp (gimple_seq *body_p, omp_contex
/* Re-gimplification and code generation routines. */
+/* Remove omp_member_access_dummy_var variables from gimple_bind_vars
+ of BIND if in a method. */
+
+static void
+maybe_remove_omp_member_access_dummy_vars (gbind *bind)
+{
+ if (DECL_ARGUMENTS (current_function_decl)
+ && DECL_ARTIFICIAL (DECL_ARGUMENTS (current_function_decl))
+ && (TREE_CODE (TREE_TYPE (DECL_ARGUMENTS (current_function_decl)))
+ == POINTER_TYPE))
+ {
+ tree vars = gimple_bind_vars (bind);
+ for (tree *pvar = &vars; *pvar; )
+ if (omp_member_access_dummy_var (*pvar))
+ *pvar = DECL_CHAIN (*pvar);
+ else
+ pvar = &DECL_CHAIN (*pvar);
+ gimple_bind_set_vars (bind, vars);
+ }
+}
+
+/* Remove omp_member_access_dummy_var variables from BLOCK_VARS of
+ block and its subblocks. */
+
+static void
+remove_member_access_dummy_vars (tree block)
+{
+ for (tree *pvar = &BLOCK_VARS (block); *pvar; )
+ if (omp_member_access_dummy_var (*pvar))
+ *pvar = DECL_CHAIN (*pvar);
+ else
+ pvar = &DECL_CHAIN (*pvar);
+
+ for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
+ remove_member_access_dummy_vars (block);
+}
+
/* If a context was created for STMT when it was scanned, return it. */
static omp_context *
@@ -6961,6 +6998,7 @@ lower_omp_for (gimple_stmt_iterator *gsi
pop_gimplify_context (new_stmt);
gimple_bind_append_vars (new_stmt, ctx->block_vars);
+ maybe_remove_omp_member_access_dummy_vars (new_stmt);
BLOCK_VARS (block) = gimple_bind_vars (new_stmt);
if (BLOCK_VARS (block))
TREE_USED (block) = 1;
@@ -7413,6 +7451,7 @@ lower_omp_taskreg (gimple_stmt_iterator
/* Declare all the variables created by mapping and the variables
declared in the scope of the parallel body. */
record_vars_into (ctx->block_vars, child_fn);
+ maybe_remove_omp_member_access_dummy_vars (par_bind);
record_vars_into (gimple_bind_vars (par_bind), child_fn);
if (ctx->record_type)
@@ -7781,6 +7820,7 @@ lower_omp_target (gimple_stmt_iterator *
/* Declare all the variables created by mapping and the variables
declared in the scope of the target body. */
record_vars_into (ctx->block_vars, child_fn);
+ maybe_remove_omp_member_access_dummy_vars (tgt_bind);
record_vars_into (gimple_bind_vars (tgt_bind), child_fn);
}
@@ -8772,6 +8812,7 @@ lower_omp_1 (gimple_stmt_iterator *gsi_p
break;
case GIMPLE_BIND:
lower_omp (gimple_bind_body_ptr (as_a <gbind *> (stmt)), ctx);
+ maybe_remove_omp_member_access_dummy_vars (as_a <gbind *> (stmt));
break;
case GIMPLE_OMP_PARALLEL:
case GIMPLE_OMP_TASK:
@@ -8976,6 +9017,16 @@ execute_lower_omp (void)
all_contexts = NULL;
}
BITMAP_FREE (task_shared_vars);
+
+ /* If current function is a method, remove artificial dummy VAR_DECL created
+ for non-static data member privatization, they aren't needed for
+ debuginfo nor anything else, have been already replaced everywhere in the
+ IL and cause problems with LTO. */
+ if (DECL_ARGUMENTS (current_function_decl)
+ && DECL_ARTIFICIAL (DECL_ARGUMENTS (current_function_decl))
+ && (TREE_CODE (TREE_TYPE (DECL_ARGUMENTS (current_function_decl)))
+ == POINTER_TYPE))
+ remove_member_access_dummy_vars (DECL_INITIAL (current_function_decl));
return 0;
}
--- gcc/cp/tree.c.jj 2018-02-09 06:44:24.855812073 +0100
+++ gcc/cp/tree.c 2018-02-09 13:44:22.938670431 +0100
@@ -5273,16 +5273,6 @@ cp_free_lang_data (tree t)
/* We do not need the leftover chaining of namespaces from the
binding level. */
DECL_CHAIN (t) = NULL_TREE;
- /* Set DECL_VALUE_EXPRs of OpenMP privatized member artificial
- decls to error_mark_node. These are DECL_IGNORED_P and after
- OpenMP lowering they aren't useful anymore. Clearing DECL_VALUE_EXPR
- doesn't work, as expansion could then consider them as something
- to be expanded. */
- if (VAR_P (t)
- && DECL_LANG_SPECIFIC (t)
- && DECL_OMP_PRIVATIZED_MEMBER (t)
- && DECL_IGNORED_P (t))
- SET_DECL_VALUE_EXPR (t, error_mark_node);
}
/* Stub for c-common. Please keep in sync with c-decl.c.
--- gcc/testsuite/g++.dg/ubsan/pr83987-2.C.jj 2018-02-09 12:36:23.124496958
+0100
+++ gcc/testsuite/g++.dg/ubsan/pr83987-2.C 2018-02-09 12:20:52.567160966
+0100
@@ -0,0 +1,24 @@
+// PR sanitizer/83987
+// { dg-do compile { target fopenmp } }
+// { dg-options "-fopenmp -fsanitize=vptr" }
+
+struct A
+{
+ int i;
+};
+
+struct B : virtual A
+{
+ void foo();
+};
+
+void B::foo()
+{
+#pragma omp parallel
+ {
+ #pragma omp sections lastprivate (i)
+ {
+ i = 0;
+ }
+ }
+}
Jakub
