aboutsummaryrefslogtreecommitdiff
path: root/gcc/cp
diff options
context:
space:
mode:
authorJakub Jelinek <jakub@redhat.com>2023-01-19 23:27:34 +0100
committerJakub Jelinek <jakub@redhat.com>2023-01-19 23:27:34 +0100
commit9b9a989adc042b304572fd6d4ade46b47be6ccb8 (patch)
treef863fb6cccd9ccd4a333c89b7a0d9c40a0314fb6 /gcc/cp
parentc81e68a9cdbb5411dce1f1da3b35854212305c7c (diff)
downloadgcc-9b9a989adc042b304572fd6d4ade46b47be6ccb8.zip
gcc-9b9a989adc042b304572fd6d4ade46b47be6ccb8.tar.gz
gcc-9b9a989adc042b304572fd6d4ade46b47be6ccb8.tar.bz2
c++: Fix up handling of references to anon union members in initializers [PR53932]
For anonymous union members we create artificial VAR_DECLs which have DECL_VALUE_EXPR for the actual COMPONENT_REF. That works just fine inside of functions (including global dynamic constructors), because during gimplification such VAR_DECLs are gimplified as their DECL_VALUE_EXPR. This is also done during regimplification. But references to these artificial vars in DECL_INITIAL expressions aren't ever replaced by the DECL_VALUE_EXPRs, so we end up either with link failures like on the testcase below, or worse ICEs with LTO. The following patch fixes those during cp_fully_fold_init where we already walk all the trees (!data->genericize means that function rather than cp_fold_function). 2023-01-19 Jakub Jelinek <jakub@redhat.com> PR c++/53932 * cp-gimplify.cc (cp_fold_r): During cp_fully_fold_init replace DECL_ANON_UNION_VAR_P VAR_DECLs with their corresponding DECL_VALUE_EXPR. * g++.dg/init/pr53932.C: New test.
Diffstat (limited to 'gcc/cp')
-rw-r--r--gcc/cp/cp-gimplify.cc10
1 files changed, 10 insertions, 0 deletions
diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc
index a282156..340b464 100644
--- a/gcc/cp/cp-gimplify.cc
+++ b/gcc/cp/cp-gimplify.cc
@@ -1010,6 +1010,16 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_)
}
break;
+ case VAR_DECL:
+ /* In initializers replace anon union artificial VAR_DECLs
+ with their DECL_VALUE_EXPRs, as nothing will do it later. */
+ if (DECL_ANON_UNION_VAR_P (stmt) && !data->genericize)
+ {
+ *stmt_p = stmt = unshare_expr (DECL_VALUE_EXPR (stmt));
+ break;
+ }
+ break;
+
default:
break;
}