[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #1 from rguenth at gcc dot gnu dot org 2009-02-14 16:55 ---
Single-file testcase, reproduces with a x86_64-pc-mingw32 cross at any
optimization level. get_symbol_constant_value returns zero for K::k.
struct K {
static const unsigned k;
};
extern C void abort (void);
int main() {
if ( K::k != 1 )
abort ();
return 1;
}
--
rguenth at gcc dot gnu dot org changed:
What|Removed |Added
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|-00-00 00:00:00 |2009-02-14 16:55:18
date||
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #2 from rguenth at gcc dot gnu dot org 2009-02-14 17:03 --- The problem is that targetm.binds_local_p returns true for var_decl 0xb7866000 k type integer_type 0xb785edd0 unsigned int readonly unsigned SI size integer_cst 0xb778b4a4 constant 32 unit size integer_cst 0xb778b1f8 constant 4 align 32 symtab 0 alias set -1 canonical type 0xb785edd0 precision 32 min integer_cst 0xb778b4c8 0 max integer_cst 0xb778b480 4294967295 readonly used public static unsigned external nonlocal decl_3 decl_5 decl_6 SI file t.ii line 2 col 27 size integer_cst 0xb778b4a4 32 unit size integer_cst 0xb778b1f8 4 align 32 context record_type 0xb785ec30 K chain type_decl 0xb785ed00 K though probably nobody thought of handling TREE_STATIC DECL_EXTERNAL being true at the same time. Thus, this looks like a possible C++ FE problem to me? A simple fix would be for i386_pe_binds_local_p to return false if DECL_EXTERNAL is set, as this is what default_binds_local_p_1 does. Or better, it should dispatch to default_binds_local_p_1 and only adjust the shlib flag according to DECL_DLLIMPORT_P. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #3 from ebotcazou at gcc dot gnu dot org 2009-02-14 17:16 --- The problem is that targetm.binds_local_p returns true for var_decl 0xb7866000 k type integer_type 0xb785edd0 unsigned int readonly unsigned SI size integer_cst 0xb778b4a4 constant 32 unit size integer_cst 0xb778b1f8 constant 4 align 32 symtab 0 alias set -1 canonical type 0xb785edd0 precision 32 min integer_cst 0xb778b4c8 0 max integer_cst 0xb778b480 4294967295 readonly used public static unsigned external nonlocal decl_3 decl_5 decl_6 SI file t.ii line 2 col 27 size integer_cst 0xb778b4a4 32 unit size integer_cst 0xb778b1f8 4 align 32 context record_type 0xb785ec30 K chain type_decl 0xb785ed00 K though probably nobody thought of handling TREE_STATIC DECL_EXTERNAL being true at the same time. Thus, this looks like a possible C++ FE problem to me? FWIW we had the same problem in Ada on this platform and we fixed Gigi. -- ebotcazou at gcc dot gnu dot org changed: What|Removed |Added CC||ebotcazou at gcc dot gnu dot ||org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #6 from ktietz at gcc dot gnu dot org 2009-02-14 20:10 ---
(In reply to comment #2)
The problem is that targetm.binds_local_p returns true for
var_decl 0xb7866000 k
type integer_type 0xb785edd0 unsigned int readonly unsigned SI
size integer_cst 0xb778b4a4 constant 32
unit size integer_cst 0xb778b1f8 constant 4
align 32 symtab 0 alias set -1 canonical type 0xb785edd0 precision 32
min integer_cst 0xb778b4c8 0 max integer_cst 0xb778b480 4294967295
readonly used public static unsigned external nonlocal decl_3 decl_5
decl_6
SI file t.ii line 2 col 27 size integer_cst 0xb778b4a4 32 unit size
integer_cst 0xb778b1f8 4
align 32 context record_type 0xb785ec30 K
chain type_decl 0xb785ed00 K
though probably nobody thought of handling TREE_STATIC DECL_EXTERNAL being
true at the same time. Thus, this looks like a possible C++ FE problem to me?
A simple fix would be for i386_pe_binds_local_p to return false if
DECL_EXTERNAL is set, as this is what default_binds_local_p_1 does.
Or better, it should dispatch to default_binds_local_p_1 and only
adjust the shlib flag according to DECL_DLLIMPORT_P.
Right in winnt.c (i386_pe_bind_local_p) should be something like this patch,
but sadly we get then emitted @GOTPCREL, which aren't handled proper by COFF
targets.
Index: gcc/gcc/config/i386/winnt.c
===
--- gcc.orig/gcc/config/i386/winnt.c
+++ gcc/gcc/config/i386/winnt.c
@@ -321,13 +321,14 @@ i386_pe_encode_section_info (tree decl,
bool
i386_pe_binds_local_p (const_tree exp)
{
+ bool flag = true;
/* PE does not do dynamic binding. Indeed, the only kind of
non-local reference comes from a dllimport'd symbol. */
if ((TREE_CODE (exp) == VAR_DECL || TREE_CODE (exp) == FUNCTION_DECL)
DECL_DLLIMPORT_P (exp))
-return false;
+flag = false;
- return true;
+ return flag default_binds_local_p_1 (exp, flag_shlib);
}
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #7 from rguenth at gcc dot gnu dot org 2009-02-14 21:12 --- What happens if you just use return default_binds_local_p_1 (exp, (TREE_CODE (exp) == VAR_DECL || TREE_CODE (exp) == FUNCTION_DECL) DECL_DLLIMPORT_P (exp)); ? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #8 from ktietz at gcc dot gnu dot org 2009-02-14 21:25 --- (In reply to comment #7) What happens if you just use return default_binds_local_p_1 (exp, (TREE_CODE (exp) == VAR_DECL || TREE_CODE (exp) == FUNCTION_DECL) DECL_DLLIMPORT_P (exp)); ? Same issue @GOTPCREL code gets emitted. ... movq__zn1k...@gotpcrel(%rip), %rax cmpl$1, (%rax) ... -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
--- Comment #9 from nightstrike at gmail dot com 2009-02-14 22:56 --- Verified to fail on win32 and win64, not just win64. Can someone with sufficient privileges adjust Target? Verified to work in 4.3, so this is a regression. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
[Bug target/39179] Wrong code in c++ for const members initialized in external file
-- ktietz at gcc dot gnu dot org changed: What|Removed |Added Priority|P3 |P2 Target Milestone|--- |4.4.0 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39179
