Hello,
Following the recommendations on
http://gcc.gnu.org/install/finalinstall.html, I'm reporting my success
at building gcc 4.7.0 on amd64-unknown-openbsd4.8 because this platform
is not listed in http://gcc.gnu.org/buildstat.html. My build is only
"mostly" successful; I encountered and worked around several problems
which I detail below. Help and suggestions are welcome.
Here's gcc -v:
Using built-in specs.
COLLECT_GCC=gcc-4.7.0
COLLECT_LTO_WRAPPER=/storage/gcc470/usr/local/bin/../libexec/gcc/x86_64-unknown-openbsd4.8/4.7.0/lto-wrapper
Target: x86_64-unknown-openbsd4.8
Configured with: ../gcc/configure --program-suffix=-4.7.0
--enable-threads --disable-werror
Thread model: posix
gcc version 4.7.0 (GCC)
I have been unable so far to secure a release from my employer to
contribute patches to GCC. So I'll just describe what I did as a
reference for others.
I configured with --disable-werror because on earlier releases of GCC I
had trouble with the definition of NULL and functions expecting a
sentinel. The switch is the easiest workaround, but might not be
necessary anymore.
I ran into two problems that have open PRs:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39618
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52471
The first problem can be worked around most easily by killing the hung
process. I do not have a "good" workaround for the second problem -- I
bypassed the ICE by disabling some code in gcc/dwarf2cfi.c, which
hobbles my ability to use a debugger. See my diffs below.
On my platform I have an issue building libiberty. In
libiberty/stack-limit.c I need to #include <sys/time.h> immediately
before <sys/resource.h>. I have also built GDB 7.4, which also uses
libiberty, and it needs the identical workaround.
While building GCC this command is eventually executed, and hangs on my
system:
./gcj-dbtool -n classmap.db || touch classmap.db
The command itself was a sufficient hint that this is optional. If I
kill the hung gcj-dbtool process, everything continues nicely.
Later, I get an error compiling ../../../gcc/boehm-gc/misc.c with a
suggestive error message:
In file included from /usr/include/xmmintrin.h:39:0,
from /usr/include/emmintrin.h:34,
from ../../../gcc/libitm/config/x86/target.h:77,
from ../../../gcc/libitm/libitm_i.h:82,
from ../../../gcc/libitm/aatree.cc:28:
/usr/include/mmintrin.h: In function '__m64 _mm_add_si64(__m64, __m64)':
/usr/include/mmintrin.h:312:72: error: cannot convert 'long long int' to
'__vector(1) long long int' for argument '1' to '__vector(1) long long
int __builtin_ia32_paddq(__vector(1) long long int, __vector(1) long
long int)'
Those header files should come from gcc/config/i386, not from
/usr/include. If I symlink gcc/config/i386/*intrin.h into the build
directory (obj/x86_64-unknown-openbsd4.8/libitm) and retry, it works.
This may point to a bug in makefile generation that goes unnoticed on
other platforms where the /usr/include headers and the gcc/config/i386
headers match.
The resulting compiler works. The only trouble I've noticed so far is
with std::thread. Any attempt to create a std::thread throws a
std::system_error. I haven't been able to figure out what's wrong
because the debugger doesn't work very well after my edit to
gcc/dwarf2cfi.c.
Here are my diffs. I do not warrant that any of these are correct, but
they work well enough for me that I can make undebuggable
single-threaded programs.
Index: boehm-gc/include/private/gcconfig.h
===================================================================
--- boehm-gc/include/private/gcconfig.h (revision 185724)
+++ boehm-gc/include/private/gcconfig.h (working copy)
@@ -330,6 +330,11 @@
# define OPENBSD
# define mach_type_known
# endif
+# if defined(__OpenBSD__) && (defined(__x86_64__))
+# define X86_64
+# define OPENBSD
+# define mach_type_known
+# endif
# if defined(FREEBSD) && (defined(i386) || defined(__i386__))
# define I386
# define mach_type_known
@@ -2065,6 +2070,12 @@
extern char etext[];
# define SEARCH_FOR_DATA_START
# endif
+# ifdef OPENBSD
+# define OS_TYPE "OPENBSD"
+# define HEURISTIC2
+ extern char etext[];
+# define DATASTART ((ptr_t)(etext))
+# endif
# ifdef SUNOS5
# define ELF_CLASS ELFCLASS64
# define OS_TYPE "SUNOS5"
Index: libiberty/stack-limit.c
===================================================================
--- libiberty/stack-limit.c (revision 185724)
+++ libiberty/stack-limit.c (working copy)
@@ -39,6 +39,7 @@
#include <stdint.h>
#endif
#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/time.h>
#include <sys/resource.h>
#endif
Index: libgcc/config.host
===================================================================
--- libgcc/config.host (revision 185724)
+++ libgcc/config.host (working copy)
@@ -538,6 +538,8 @@
;;
i[34567]86-*-openbsd*)
;;
+x86_64-*-openbsd*)
+ ;;
i[34567]86-*-linux*)
extra_parts="$extra_parts crtprec32.o crtprec64.o crtprec80.o
crtfastmath.o"
tmake_file="${tmake_file} i386/t-crtpc i386/t-crtfm
i386/t-crtstuff t-dfprules"
Index: gcc/dwarf2cfi.c
===================================================================
--- gcc/dwarf2cfi.c (revision 185724)
+++ gcc/dwarf2cfi.c (working copy)
@@ -2904,9 +2904,11 @@
create_pseudo_cfg ();
/* Do the work. */
+/*
create_cfi_notes ();
connect_traces ();
add_cfis_to_fde ();
+*/
/* Free all the data we allocated. */
{
Index: gcc/config.gcc
===================================================================
--- gcc/config.gcc (revision 185724)
+++ gcc/config.gcc (working copy)
@@ -1225,6 +1225,13 @@
gas=yes
gnu_ld=yes
;;
+x86_64-*-openbsd*)
+ tm_file="${tm_file} i386/unix.h i386/att.h dbxelf.h elfos.h"
+ tm_file="${tm_file} openbsd.h openbsd-stdint.h
openbsd-libpthread.h i386/openbsdelf.h"
+ extra_options="${extra_options} openbsd.opt"
+ gas=yes
+ gnu_ld=yes
+ ;;
i[34567]86-*-linux* | i[34567]86-*-kfreebsd*-gnu |
i[34567]86-*-knetbsd*-gnu | i[34567]86-*-gnu* |
i[34567]86-*-kopensolaris*-gnu)
# Intel 80386's running GNU/*
# with ELF format using glibc 2
--
Kyle Markley
