Here is the test program:
template <typename T> class gnu_obj_2
static int my_static;
template <typename T> int gnu_obj_2<T>::my_static = 117;
// instantiate templates explicitly so their static members will exist
template class gnu_obj_2 <int>;
template class gnu_obj_2 <long>;
int main ()
gnu_obj_2 <int> test_int;
gnu_obj_2 <long> test_long;
I compile this program with "gcc -S -gstabs+". Then I look in the generated
assembly code for the static data members gnu_obj_2<int>::my_static and
(I don't think the -gstabs+ is important but I just happened to start with this
flag and have kept it all the way till now, sigh. This code originally came
from the gdb test suite, gdb.cp/m-static.cc).
The explicit instantiations of gnu_obj_2<int> and gnu_obj_2<long> are supposed
to instantiate the static data members along with everything else, but they don't.
The last working gcc was 2004-05-19 01:00:00 UTC and the first broken gcc was
2004-05-19 02:00:00 UTC. The problem is with this patch:
IMA repairs: Don't use DECL_ASSEMBLER_NAME for a key in cgraph(take two)
I'll add three attachments: the test program; the last good assembly code; and
the first bad assembly code.
Created attachment 6424 [details]
Compile with: "gcc -S -gstabs+".
Look for gnu_obj_2<int>::my_static and gnu_obj_2<long>::my_static in the
Created attachment 6425 [details]
assembly code, last good compiler, 2004-05-19 01:00:00 UTC
Generated assembly code with "gcc -S -gstabs+ template-static.cc".
This is with the last good compiler.
Created attachment 6426 [details]
Generated code, first bad compiler, 2004-05-19 02:00:00 UTC
Code generated with "gcc -S -gstabs+ template-static.cc".
This is with the first bad compiler.
Confirmed, I will try to figure out what is going on but if Zack beats me, I would not be made.
mark_decl_referenced is being called for the variable.
The problem is that decl is not finalized before being marked as needed.
I know that rest_of_decl_compilation is being called for the decl but not assemble_variable for some
reason. I have not checked how it was done before Zack's patch.
The difference between before and after is that DECL_EXTERNAL (decl) in rest_of_decl_compilation is
true after but false before which causes it not be outputted.
Ignore that last comment, I was wrong, it does not even get to rest_of_decl_compilation for that decl.
Okay, wrapup_global_declarations checks TREE_SYMBOL_REFERENCED of DECL_ASSEMBLER_NAME of the
decl which is where the problem is.
This should work (I have tested it on the testcase though), I have not bootstrapped and tested it yet:
RCS file: /cvs/gcc/gcc/gcc/toplev.c,v
retrieving revision 1.899
diff -u -p -r1.899 toplev.c
--- toplev.c 30 May 2004 18:32:27 -0000 1.899
+++ toplev.c 2 Jun 2004 00:41:09 -0000
@@ -1455,16 +1455,17 @@ wrapup_global_declarations (tree *vec, i
if (TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl))
+ struct cgraph_varpool_node *node;
bool needed = 1;
+ node = cgraph_varpool_node (decl);
- if (flag_unit_at_a_time
- && cgraph_varpool_node (decl)->finalized)
+ if (node && node->finalized)
needed = 0;
else if ((flag_unit_at_a_time && !cgraph_global_info_ready)
&& (TREE_USED (decl)
|| TREE_USED (DECL_ASSEMBLER_NAME (decl))))
/* needed */;
- else if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+ else if (node && node->needed)
/* needed */;
else if (DECL_COMDAT (decl))
needed = 0;
Mine, I posted a patch: <http://gcc.gnu.org/ml/gcc-patches/2004-06/msg00088.html>.
Andrew, this patch was approved by Mark, I assume you just forgot to apply and
close the bug...
Subject: Bug 15721
Module name: gcc
Changes by: firstname.lastname@example.org 2004-06-19 16:17:01
gcc : ChangeLog toplev.c
2004-06-19 Andrew Pinski <email@example.com>
* toplev.c (wrapup_global_declarations): Do not check
TREE_SYMBOL_REFERENCED of the DECL_ASSEMBLER_NAME but check
cgraph_varpool_node's needed field.
No I was just testing it again.
Subject: Re: [3.5 regression] template instantation omits static data members
It works for me.
Thanks, Michael C