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[[!meta copyright="Copyright © 2007, 2008, 2010, 2011, 2013, 2016 Free Software
Foundation, Inc."]]
[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
id="license" text="Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
is included in the section entitled [[GNU Free Documentation
License|/fdl]]."]]"""]]
(!) See also [[/glibc/debugging]].
Here are some hints about how to approach testing after nontrivial changes to
glibc have been done.
---
First step is having the build of glibc succeed. This is actually more
difficult than one might expect as it involves (towards the end of the build
process -- unless you are cross-compiling, of course -- that the
newly created libraries and loader actually work: they'll be used to run the
`rpcgen` program. If that step doesn't succeed, it'll look similar to this:
[...]
CPP='gcc -E -x c-header' [...]/build/elf/ld.so.1 --library-path [...] [...]/build/sunrpc/rpcgen [...]
Segmentation fault
---
Unless cross-compiling, the next thing you'll probably want to do
is running the test suite, or parts of it.
There is a list of [[known failures|open_issues/glibc]].
---
When building the debian glibc, to save yourself a double-compilation, comment
in debian/sysdeps/hurd-i386.mk the lines about xen. Then to avoid the whole
testsuite, use:
DEB_BUILD_OPTIONS=nocheck dpkg-buildpackage
To save even more build, stop the build after configure has run, and then you
can restart the build of only libc.so and libc.a with:
cd build-tree/hurd-i386-libc
make lib
or of only libc.so with:
make objdir=$PWD/build-tree/hurd-i386-libc $PWD/build-tree/hurd-i386-libc/libc.so
or of the whole tree with:
cd build-tree/hurd-i386-libc
make
or of just one subdir with for instance:
make subdir=libpthread -C libpthread ..=../ objdir=$PWD/build-tree/hurd-i386-libc
(note that most subdirs need libc.so built)
---
In some cases, printing to stdout/stderr is problematic. One can use a kernel
with kdb enabled, and `mach_print` to get messages on the console:
#include <mach/mach_traps.h>
...
mach_print("foo\n");
If your `mach_traps.h` does not have the declaration, use:
extern void mach_print(const char *s);
If you can't use the libc-provided `mach_print` for some reason, you can use as last resort:
asm("\
my_mach_print:\n\
mov $-30,%eax\n\
lcall $7,$0\n\
ret\n\
");
extern void my_mach_print(const char *s);
This call does not support any formatting. You can use this kind of helper to
format a message before passing to gnumach:
#include <mach/mach_traps.h>
#include <stdio.h>
static void myprintf(const char *fmt, ...)
{
va_list ap;
char buf[1024];
va_start(ap, fmt);
vsnprintf(buf, sizeof(buf), fmt, ap);
mach_print(buf);
va_end(ap);
}
---
If you've been doing simple changes to glibc functions that end up in
`libc.so`, you may test them like this (like for a `strerror_l` implementation
in this case):
$ LD_PRELOAD=./libc.so ./ld.so ./a.out 10 1073741928 de_DE.utf8
1073741928 (0x40000068): Computer bought the farm
1073741928 (0x40000068): Der Computer hat den Bauernhof erworben
You usually will only have luck using the new `libc.so` (from
`[glibc-build]/libc.so`) in combination together with the new `ld.so` (from
`[glibc-build]/elf/ld.so`):
$ LD_PRELOAD=./libc.so ./a.out 10 1073741928 de_DE.utf8
Killed
$ LD_PRELOAD=./libc.so /lib/ld.so ./a.out 10 1073741928 de_DE.utf8
Killed
Make sure static linking is working OK at all. Running the
`[glibc-build]/elf/sln` program (a stripped-down `ln` that is statically
linked) ought to test that. Also, static linking under various conditions will
already have been tested when running the test suite, especially in `elf/` and
`dlfcn/`.
Make sure static linking with cthreads is working. If you can get an
`ext2fs.static` compiled and linked against the new glibc, that is good.
[TODO].
Then debug its startup as a normal program on your working hurd.
$ [...]/ext2fs.static --help
[...]
Then try its full server startup.
$ settrans -ca node [...]/ext2fs.static BACKING_STORE
$ ls -l node/
[...]
Make sure dynamic linking for servers is working. If you haven't broken the
ABI, you can just use an existing `/hurd/foobar` binary, started the way
glibc's `testrun.sh` does it.
[TODO]: Is this the correct way to do that?
$ settrans -ca node [glibc]/build/testrun.sh /hurd/ext2fs BACKING_STORE
$ cd node/
[...]
---
Test it in a [[subhurd]].
---
Test it on a real system.
|
