From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1314) id D5A623857B9D; Mon, 8 Aug 2022 15:14:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D5A623857B9D MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Andrew Pinski To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-1990] Fix middle-end/103645: empty struct store not removed when using compound literal X-Act-Checkin: gcc X-Git-Author: Andrew Pinski X-Git-Refname: refs/heads/trunk X-Git-Oldrev: 5471f55f001af412e1125b04972ebaab9d4f7337 X-Git-Newrev: 21c7aab09805d0c8c7695c8a69c8715d673a739a Message-Id: <20220808151445.D5A623857B9D@sourceware.org> Date: Mon, 8 Aug 2022 15:14:45 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Aug 2022 15:14:45 -0000 https://gcc.gnu.org/g:21c7aab09805d0c8c7695c8a69c8715d673a739a commit r13-1990-g21c7aab09805d0c8c7695c8a69c8715d673a739a Author: Andrew Pinski Date: Mon Dec 20 20:27:33 2021 -0800 Fix middle-end/103645: empty struct store not removed when using compound literal For compound literals empty struct stores are not removed as they go down a different path of the gimplifier; trying to optimize the init constructor. This fixes the problem by not adding the gimple assignment at the end of gimplify_init_constructor if it was an empty type. Note this updates gcc.dg/pr87052.c where we had: const char d[0] = { }; And was expecting a store to d but after this, there is no store as the decl's type is zero in size. OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions. gcc/ChangeLog: PR middle-end/103645 * gimplify.cc (gimplify_init_constructor): Don't build/add gimple assignment of an empty type. gcc/testsuite/ChangeLog: * gcc.dg/pr87052.c: Update d var to expect nothing. Diff: --- gcc/gimplify.cc | 7 +++++-- gcc/testsuite/gcc.dg/pr87052.c | 6 +++--- 2 files changed, 8 insertions(+), 5 deletions(-) diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc index 2ac7ca0855e..f0fbdb48012 100644 --- a/gcc/gimplify.cc +++ b/gcc/gimplify.cc @@ -5488,8 +5488,11 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, if (ret == GS_ERROR) return GS_ERROR; /* If we have gimplified both sides of the initializer but have - not emitted an assignment, do so now. */ - if (*expr_p) + not emitted an assignment, do so now. */ + if (*expr_p + /* If the type is an empty type, we don't need to emit the + assignment. */ + && !is_empty_type (TREE_TYPE (TREE_OPERAND (*expr_p, 0)))) { tree lhs = TREE_OPERAND (*expr_p, 0); tree rhs = TREE_OPERAND (*expr_p, 1); diff --git a/gcc/testsuite/gcc.dg/pr87052.c b/gcc/testsuite/gcc.dg/pr87052.c index 18e092c4674..796fe6440c1 100644 --- a/gcc/testsuite/gcc.dg/pr87052.c +++ b/gcc/testsuite/gcc.dg/pr87052.c @@ -23,8 +23,7 @@ void test (void) const char d[0] = { }; - /* Expect the following: - d = ""; */ + /* Expect nothing. */ const char e[0] = ""; @@ -36,6 +35,7 @@ void test (void) /* { dg-final { scan-tree-dump-times "a = \"\\\\x00ab\";" 1 "gimple" } } { dg-final { scan-tree-dump-times "b = \"a\\\\x00bc\";" 1 "gimple" } } { dg-final { scan-tree-dump-times "c = \"\";" 1 "gimple" } } - { dg-final { scan-tree-dump-times "d = { *};" 1 "gimple" } } + { dg-final { scan-tree-dump-times "d = " 1 "gimple" } } + { dg-final { scan-tree-dump-times "d = {CLOBBER\\(eol\\)}" 1 "gimple" } } { dg-final { scan-tree-dump-times "e = " 1 "gimple" } } { dg-final { scan-tree-dump-times "e = {CLOBBER\\(eol\\)}" 1 "gimple" } } */