[Bug libstdc++/22388] New: When cross-compiling libstdc++ for mingw, enable large file support (LFS)

2005-07-09 Thread ra at atterer dot net 
I have tracked down the cause of Debian bug <http://bugs.debian.org/306210>:
When you compile C++ programs using Debian's mingw32 cross-compiler package
(currently based on mingw32-3.4.2.20040916.1), then the compiled C++ programs do
not have large file support enabled.
The simple fix is to enable LFS in libstdc++-v3/crossconfig.m4.

This bug probably also applies to GCC versions 3.4.3 .. 4.0

Patch:

--- gcc-3.4.2-20040916-1/libstdc++-v3/crossconfig.m4.orig  2004-08-15
10:41:14.0 +0200
+++ gcc-3.4.2-20040916-1/libstdc++-v3/crossconfig.m4   2005-07-09
19:53:15.0 +0200
@@ -234,6 +234,7 @@
 GLIBCXX_CHECK_LINKER_FEATURES
 GLIBCXX_CHECK_COMPLEX_MATH_SUPPORT
 GLIBCXX_CHECK_WCHAR_T_SUPPORT
+AC_DEFINE(_GLIBCXX_USE_LFS)
 ;;
   *-netbsd*)
 AC_CHECK_HEADERS([nan.h ieeefp.h endian.h sys/isa_defs.h \

-- 
   Summary: When cross-compiling libstdc++ for mingw, enable large
file support (LFS)
   Product: gcc
   Version: 3.4.2
Status: UNCONFIRMED
  Severity: normal
  Priority: P2
 Component: libstdc++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: ra at atterer dot net
CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i586-mingw32msvc


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22388

[Bug libstdc++/22388] When cross-compiling libstdc++ for mingw, enable large file support (LFS)

2005-07-10 Thread ra at atterer dot net 

--- Additional Comments From ra at atterer dot net  2005-07-10 08:39 ---
(In reply to comment #1)
> mingw runtime does not have struct stat64 or fstat64(), so this define is not 
> correct.

Hmm - but I've successfully cross-compiled libstdc++ on Linux with this #define,
and I'm 100% sure it made a difference - my cross-compiled program can now
access large files under Windows, previously it couldn't.

Look e.g. at the code in libstdc++-v3/config/io/basic_file_stdio.cc:

#if defined (_GLIBCXX_USE_LFS) && defined (__MINGW32__)
struct _stati64 __buffer;
int __ret = _fstati64 (this->fd(), &__buffer);
...
It's all there, and _GLIBCXX_USE_LFS is needed to enable it. BTW, your native
mingw builds do have large file support, LFS only breaks if libstdc++ is
cross-compiled.

The rest of libstdc++ does not use fstat64(), only fstat() - I guess it relies
on someone re#defing it to fstat64 (or, in fact, _fstati64).

Richard (OP)

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22388