Hi tech@,
I'm working on a port for lang/dart and got stuck on ucontext.h compile
errors.
The first one was quite easy, changing sys/ucontext.h to signal.h since
ucontext_t is
defined there
sys/signal.h:
typedef struct sigcontext ucontext_t;
This allowed me to move forward and stop on the next bit:
In file included from runtime/vm/thread_interrupter.h:9:0,
from runtime/vm/profiler.h:13,
from runtime/vm/dart.ca c:22:
runtime/vm/signal_handler.h:49:44: error: 'mcontext_t' does not name a
type
static uintptr_t GetProgramCounter(const mcontext_t& mcontext);
^
runtime/vm/signal_handler.h:50:42: error: 'mcontext_t' does not name a
type
Which lead me to a hunt on how other parts of base/ports handle this.
I grepped /usr/src and found something interesting.
/gnu/gcc/gcc/config/pa/hpux-unwind.h
which contains a:
#include <sys/ucontext.h>
Now taking this example C program:
$ cat dead.c
#include <sys/ucontext.h>
int
main(int argc, char *argv[])
{
return 0;
}
$
and trying to compile it:
$ make dead
cc -O2 -pipe -o dead dead.c
dead.c:1:26: error: sys/ucontext.h: No such file or directory
*** Error 1 in /home/mulander/code/c (<sys.mk>:85 'dead')
We can see that sys/ucontext.h is not present. Hence the hpux-unwind.h
header file must be dead code.
Grepping src I found some more occurrences, all in base gcc (minus some
changelog/comment entries).
Should header files including sys/ucontext.h be removed along with their
paired .c files?
./gnu/gcc/fixincludes/ChangeLog: * tests/base/sys/ucontext.h: New
file.
./gnu/gcc/fixincludes/fixincl.x: "|sys/ucontext.h|";
./gnu/gcc/fixincludes/inclhack.def:/* The /usr/include/sys/ucontext.h on
ia64-*linux-gnu systems defines
./gnu/gcc/fixincludes/inclhack.def: files = "sys/ucontext.h";
./gnu/gcc/fixincludes/tests/base/sys/ucontext.h:
"fixinc/tests/inc/sys/ucontext.h"
./gnu/gcc/gcc/config/alpha/linux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/i386/linux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/i386/linux-unwind.h:/* There's no sys/ucontext.h
for glibc 2.0, so no
./gnu/gcc/gcc/config/i386/linux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/ia64/linux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/mips/linux-unwind.h: * struct ucontext from
sys/ucontext.h so this private copy is used. */
./gnu/gcc/gcc/config/pa/hpux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/pa/linux-unwind.h:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/rs6000/host-darwin.c:#include <sys/ucontext.h>
./gnu/gcc/gcc/config/sh/linux-unwind.h:#include <sys/ucontext.h>
./gnu/usr.bin/binutils/gdb/s390-nat.c:#include <sys/ucontext.h>
./gnu/usr.bin/binutils/gdb/sparc-nat.c: fp_status' in
<sys/ucontext.h>, which is automatically included by
./gnu/usr.bin/binutils/gdb/user-regs.c: <sys/ucontext.h> includes
<sys/procfs.h> includes <sys/user.h>, which
./gnu/usr.bin/binutils/gdb/osf-share/cma_tcb_defs.h:# include
<sys/ucontext.h>
./gnu/usr.bin/gcc/gcc/ChangeLog: sys/ucontext.h inclusion in
ifndef USE_GNULIBC_1.
./gnu/usr.bin/gcc/gcc/ChangeLog.7: including signal.h and
sys/ucontext.h, not needed.
./gnu/usr.bin/gcc/gcc/ChangeLog.7: to avoid clash with Irix header
file sys/ucontext.h. Rename gp_regs
./gnu/usr.bin/gcc/gcc/config/alpha/linux.h:#include <sys/ucontext.h>
./gnu/usr.bin/gcc/gcc/config/i386/linux.h:/* There's no sys/ucontext.h
for some (all?) libc1, so no
./gnu/usr.bin/gcc/gcc/config/i386/linux.h:#include <sys/ucontext.h>
./gnu/usr.bin/gcc/gcc/config/i386/linux64.h:#include <sys/ucontext.h>
./gnu/usr.bin/gcc/gcc/config/ia64/linux.h:#include <sys/ucontext.h>
PS.
I would greatly appreciate If anyone pointed me at a file that still
defines
mcontext_t or an acceptable workaround :)
Regards,
--
Adam Wolk
[email protected]
