We should be able to assume that a template instantiation or other COMDAT
has non-zero address even if MAKE_DECL_ONE_ONLY for the target sets
DECL_WEAK and we haven't yet decided to emit a definition in this
translation unit.
Tested x86_64-pc-linux-gnu, OK for trunk?
PR c++/92003
* symtab.c (symtab_node::nonzero_address): A DECL_COMDAT decl has
non-zero address even if weak and not yet defined.
---
gcc/symtab.c | 10 +++++-----
gcc/testsuite/g++.dg/cpp0x/constexpr-static13.C | 17 +++++++++++++++++
2 files changed, 22 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-static13.C
diff --git a/gcc/symtab.c b/gcc/symtab.c
index eae891ab211..a879c095a1a 100644
--- a/gcc/symtab.c
+++ b/gcc/symtab.c
@@ -2058,22 +2058,22 @@ symtab_node::nonzero_address ()
bind to NULL. This is on by default on embedded targets only.
Otherwise all non-WEAK symbols must be defined and thus non-NULL or
- linking fails. Important case of WEAK we want to do well are comdats.
- Those are handled by later check for definition.
+ linking fails. Important case of WEAK we want to do well are comdats,
+ which also must be defined somewhere.
When parsing, beware the cases when WEAK attribute is added later. */
- if (!DECL_WEAK (decl)
+ if ((!DECL_WEAK (decl) || DECL_COMDAT (decl))
&& flag_delete_null_pointer_checks)
{
refuse_visibility_changes = true;
return true;
}
- /* If target is defined and either comdat or not extern, we know it will be
+ /* If target is defined and not extern, we know it will be
output and thus it will bind to non-NULL.
Play safe for flag_delete_null_pointer_checks where weak definition may
be re-defined by NULL. */
- if (definition && (!DECL_EXTERNAL (decl) || DECL_COMDAT (decl))
+ if (definition && !DECL_EXTERNAL (decl)
&& (flag_delete_null_pointer_checks || !DECL_WEAK (decl)))
{
if (!DECL_WEAK (decl))
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-static13.C
b/gcc/testsuite/g++.dg/cpp0x/constexpr-static13.C
new file mode 100644
index 00000000000..644f9f7f893
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-static13.C
@@ -0,0 +1,17 @@
+// PR c++/92003
+// { dg-do compile { target c++11 } }
+// { dg-prune-output "narrowing conversion" }
+
+constexpr char const* get_c_str() { return "abc"; }
+constexpr bool use_get_c_str_in_constexpr_context{get_c_str()}; // works
+
+template <char... Cs>
+struct string {
+ static constexpr char const* c_str() { return c; }
+
+ private:
+ static constexpr char c[]{Cs..., '\0'};
+};
+
+constexpr char const* cstr{string<'a', 'b', 'c'>::c_str()};
+constexpr bool use_cstr_in_constexpr_context{cstr}; // doesn't work
base-commit: fa0c6e297b22d5883857d0db4a6a8be0967cb16f
--
2.18.1
