On 23.04.19 12:01, Daniel P. Berrangé wrote:
> On Tue, Apr 23, 2019 at 11:54:53AM +0200, Philippe Mathieu-Daudé wrote:
>> Hi Richard, Daniel,
>>
>> On 4/17/19 7:32 AM, Richard Henderson wrote:
>>> If one uses -L $PATH to point to a full chroot, the startup time
>>> is significant. In addition, the existing probing algorithm fails
>>> to handle symlink loops.
>>>
>>> Instead, probe individual paths on demand. Cache both positive
>>> and negative results within $PATH, so that any one filename is
>>> probed only once.
>>>
>>> Use glib filename functions for clarity.
>>>
>>> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
>>> ---
>>> util/path.c | 211 ++++++++++++++--------------------------------------
>>> 1 file changed, 57 insertions(+), 154 deletions(-)
>
>
>>> +#if GLIB_CHECK_VERSION(2, 58, 0)
>>
>> Should we raise GLIB_VERSION_MAX_ALLOWED in "glib-compat.h"?
>>
>> Currently it is:
>>
>> /* Ask for warnings if code tries to use function that did not
>> * exist in the defined version. These risk breaking builds
>> */
>> #define GLIB_VERSION_MAX_ALLOWED GLIB_VERSION_2_40
>
> Use of 2.40 is set in accordance with our targetted platform support
> policy. If Peter has stopped using the Ubuntu 14.04 build host, we
> could bump it to 2.42. Once our dev tree opens up we could in fact
> drop Jessie since we'll be supporting Buster by the time next QEMU
> is released. That would still only take us upto perhaps Glib 2.48
>
> Glib 2.58 is waaaay to new to rely on.
>
> commit e7b3af81597db1a6b55f2c15d030d703c6b2c6ac
> Author: Daniel P. Berrangé <berra...@redhat.com>
> Date: Fri May 4 15:34:46 2018 +0100
>
> glib: bump min required glib library version to 2.40
>
> Per supported platforms doc[1], the various min glib on relevant distros
> is:
>
> RHEL-7: 2.50.3
> Debian (Stretch): 2.50.3
> Debian (Jessie): 2.42.1
> OpenBSD (Ports): 2.54.3
> FreeBSD (Ports): 2.50.3
> OpenSUSE Leap 15: 2.54.3
> SLE12-SP2: 2.48.2
> Ubuntu (Xenial): 2.48.0
> macOS (Homebrew): 2.56.0
>
> This suggests that a minimum glib of 2.42 is a reasonable target.
>
> The GLibC compile farm, however, uses Ubuntu 14.04 (Trusty) which only
> has glib 2.40.0, and this is needed for testing during merge. Thus an
> exception is made to the documented platform support policy to allow for
> all three current LTS releases to be supported.
>
> Docker jobs that not longer satisfy this new min version are removed.
>
> [1] https://qemu.weilnetz.de/doc/qemu-doc.html#Supported-build-platforms
>
> Reviewed-by: Thomas Huth <th...@redhat.com>
> Signed-off-by: Daniel P. Berrangé <berra...@redhat.com>
>
>
>>
>> From commit e71e8cc035558eabd6b3e19f6d3254c754c027ef:
>>
>> glib: enforce the minimum required version and warn about old APIs
>>
>> There are two useful macros that can be defined before including
>> glib.h that are related to the min required glib version
>>
>> - GLIB_VERSION_MIN_REQUIRED
>>
>> When this is defined, if code uses an API that was deprecated
>> in this version, or older, a compiler warning will be emitted.
>> This alerts maintainers to update their code to whatever new
>> replacement API is now recommended best practice.
>>
>> - GLIB_VERSION_MAX_ALLOWED
>>
>> When this is defined, if code uses an API that was introduced
>> in a version that is newer than the declared version, a compiler
>> warning will be emitted. This alerts maintainers if new code
>> accidentally uses functionality that won't be available on some
>> supported platforms.
>>
>> The GLIB_VERSION_MAX_ALLOWED constant makes it a bit harder to opt
>> in to using specific new APIs with a GLIB_CHECK_VERSION conditional.
>> To workaround this Pragmas can be used to temporarily turn off the
>> -Wdeprecated-declarations compiler warning, while a static inline
>> compat function is implemented. This workaround is illustrated with the
>> implementation of the g_strv_contains method to satisfy the test suite.
>>
>>> + base = g_canonicalize_filename(prefix, NULL);
>>> +#else
>>> + if (prefix[0] != '/') {
>>> + char *cwd = g_get_current_dir();
>>> + base = g_build_filename(cwd, prefix, NULL);
>>> + g_free(cwd);
>>> + } else {
>>> + base = g_strdup(prefix);
>>> + }
>>> +#endif
>
> To use functionality from newer glib releases we can't put the #ifdef
> conditionals inline in the main source files.
>
> They have to be put into glib-compat.h instead. There's a detailed
> comment in that file illustrating how todo this without triggering
> the compile warnings about deprecations.
>
>
> Regards,
> Daniel
>
Trying to build (Richard's tcg-vec-next branch) on Fedora29 I get
util/path.c: In function 'init_paths':
util/path.c:24:5: error: 'g_canonicalize_filename' is deprecated: Not
available before 2.58 [-Werror=deprecated-declarations]
base = g_canonicalize_filename(prefix, NULL);
^~~~
In file included from /usr/include/glib-2.0/glib.h:48,
from /home/dhildenb/git/qemu/include/glib-compat.h:32,
from /home/dhildenb/git/qemu/include/qemu/osdep.h:140,
from util/path.c:6:
/usr/include/glib-2.0/glib/gfileutils.h:176:8: note: declared here
gchar *g_canonicalize_filename (const gchar *filename,
^~~~~~~~~~~~~~~~~~~~~~~
util/path.c: In function 'path':
util/path.c:60:9: error: 'g_canonicalize_filename' is deprecated: Not
available before 2.58 [-Werror=deprecated-declarations]
full_name = g_canonicalize_filename(g_path_skip_root(name), base);
^~~~~~~~~
In file included from /usr/include/glib-2.0/glib.h:48,
from /home/dhildenb/git/qemu/include/glib-compat.h:32,
from /home/dhildenb/git/qemu/include/qemu/osdep.h:140,
from util/path.c:6:
/usr/include/glib-2.0/glib/gfileutils.h:176:8: note: declared here
gchar *g_canonicalize_filename (const gchar *filename,
^~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
CC backends/rng-egd.o
make: *** [/home/dhildenb/git/qemu/rules.mak:69: util/path.o] Error 1
make: *** Waiting for unfinished jobs....
CC backends/rng-random.o
--
Thanks,
David / dhildenb
