Re: pkg/47233: xulrunner DragonFly x86_64 call of overloaded 'FromTicks(long long int)' is ambiguous

[David Shao <davshao%gmail.com@localhost>]

The following reply was made to PR pkg/47233; it has been noted by GNATS.

From: David Shao <davshao%gmail.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: John Marino <netbsd%marino.st@localhost>, John Marino 
<marino%netbsd.org@localhost>
Subject: Re: pkg/47233: xulrunner DragonFly x86_64 call of overloaded
 'FromTicks(long long int)' is ambiguous
Date: Mon, 26 Nov 2012 21:51:46 -0800

 As I have reported on the DragonFly bug tracking system,
 http://bugs.dragonflybsd.org/issues/2463
 a minimal C++ test file cpperrno.cpp has been written that shows why
 pkgsrc current devel/xulrunner for firefox 17.0esr breaks only on
 DragonFly, not on other platforms such as NetBSD.  Executing
 $ c++ cpperrno.cpp
 $ ./a.out
 on platforms other than DragonFly produces output
 errno = 22
 while DragonFly produces an error:
 $ c++ cpperrno.cpp
 /tmp//ccTk4OGn.o: In function `(anonymous namespace)::__error()':
 cpperrno.cpp:(.text+0x10): undefined reference to `(anonymous 
namespace)::errno'
 
 A brief inspection of DragonFly's source code reveals in
 /usr/src/sys/sys/errno.h a declaration using the __thread storage
 class keyword for thread-local storage (TLS):
 
 #if !defined(_KERNEL) || defined(_KERNEL_VIRTUAL)
 extern __thread int errno;
 
 Obviously the immediate reaction would appear to be "Fix DragonFly."
 But the use of __thread is there for a reason, excising it would
 appear to have possibly hard to predict breakage for other userland
 programs on DragonFly, and a more elaborate mechanism for TLS would
 appear to require some time to implement.  In the interim, I would
 like to ask what are the limits for hackery that would simply allow
 devel/xulrunner to build again on DragonFly, hackery such as adding a
 fair number of  #ifdef's only for DragonFly?
 
 /* begin cpperrno.cpp */
 namespace {
 
 #pragma GCC visibility push(default)
 #include <errno.h>
 #pragma GCC visibility pop
 
 void innamespace() {
        errno = EINVAL;
 }
 
 } /* end namespace */
 
 extern "C" {
 
 void seterrno() {
        innamespace();
 }
 
 } /* end extern */
 
 #include <stdio.h>
 #include <errno.h>
 
 int main() {
        seterrno();
        printf("errno = %d\n", errno);
        return errno;
 }
 /* end cpperrno.cpp */