On Fri, Dec 20, 2019 at 3:10 PM Richard Biener
<richard.guent...@gmail.com> wrote:
>
> On December 20, 2019 2:13:47 AM GMT+01:00, "Bin.Cheng"
> <amker.ch...@gmail.com> wrote:
> >On Fri, Dec 13, 2019 at 11:26 AM bin.cheng
> ><bin.ch...@linux.alibaba.com> wrote:
> >>
> >> Hi,
> >>
> >> As reported in PR92926, constant ctor is shared translation unit wide
> >because of constexpr_call_table,
> >> however, during gimplify, the shared ctor could be modified. This
> >patch fixes the issue by unsharing
> >> it before modification in gimplify. A test is reduced from cppcoro
> >library and added.
> >>
> >> Bootstrap and test ongoing. Not sure if this is the correct fix
> >though, any comments?
> >Ping. Any comment?
>
> Looks reasonable to me.
Given PR92926 is marked as duplicate of PR93143, I updated test case
of the patch.
Thanks,
bin
2019-12-13 Bin Cheng <bin.li...@linux.alibaba.com>
PR tree-optimization/93143
* gimplify.c (gimplify_init_constructor): Unshare ctor node before
clearing.
gcc/testsuite
2019-12-13 Bin Cheng <bin.li...@linux.alibaba.com>
PR tree-optimization/93143
* g++.dg/pr93143.C: New test.
From 77252c3bb41887af1daa9e83615a8aa32dc330f9 Mon Sep 17 00:00:00 2001
From: "bin.cheng" <chengbin.cb@alibaba-inc.com>
Date: Thu, 9 Jan 2020 14:13:08 +0800
Subject: [PATCH] Fix pr93143.
---
gcc/gimplify.c | 2 ++
gcc/testsuite/g++.dg/pr93143.C | 73 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/pr93143.C
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 73fb2e7..55d7a93 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -5083,6 +5083,8 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
/* Zap the CONSTRUCTOR element list, which simplifies this case.
Note that we still have to gimplify, in order to handle the
case of variable sized types. Avoid shared tree structures. */
+ ctor = unshare_expr (ctor);
+ TREE_OPERAND (*expr_p, 1) = ctor;
CONSTRUCTOR_ELTS (ctor) = NULL;
TREE_SIDE_EFFECTS (ctor) = 0;
object = unshare_expr (object);
diff --git a/gcc/testsuite/g++.dg/pr93143.C b/gcc/testsuite/g++.dg/pr93143.C
new file mode 100644
index 0000000..40710cf
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr93143.C
@@ -0,0 +1,73 @@
+// { dg-do run }
+// { dg-options "-O3 -std=c++14" }
+
+struct array
+{
+ constexpr unsigned char operator[](int i) const noexcept
+ {
+ return arr[i];
+ }
+
+ unsigned char arr[16];
+};
+
+
+class v6 {
+public:
+ using bytes_type = array;
+ constexpr v6(bytes_type const & bytes);
+ constexpr bool is_loopback() const noexcept;
+ static constexpr v6 loopback() noexcept
+ {
+ return v6(v6::bytes_type{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1});
+ }
+private:
+ bytes_type bytes_;
+};
+
+
+
+constexpr v6::v6(bytes_type const & bytes)
+ : bytes_(bytes)
+{}
+
+constexpr
+bool v6::is_loopback() const noexcept
+{
+ return bytes_[0] == 0 &&
+ bytes_[1] == 0 &&
+ bytes_[2] == 0 &&
+ bytes_[3] == 0 &&
+ bytes_[4] == 0 &&
+ bytes_[5] == 0 &&
+ bytes_[6] == 0 &&
+ bytes_[7] == 0 &&
+ bytes_[8] == 0 &&
+ bytes_[9] == 0 &&
+ bytes_[10] == 0 &&
+ bytes_[11] == 0 &&
+ bytes_[12] == 0 &&
+ bytes_[13] == 0 &&
+ bytes_[14] == 0 &&
+ bytes_[15] == 1;
+}
+
+void v6_type()
+{
+ [[maybe_unused]] constexpr auto loopback = v6::loopback();
+}
+
+int main()
+{
+ v6_type();
+
+ constexpr auto a = v6::loopback();
+ if (!a.is_loopback())
+ __builtin_abort();
+
+ auto b = v6::loopback();
+ if (!b.is_loopback())
+ __builtin_abort();
+
+ return 0;
+}
--
1.8.3.1
