On 10/01/2013, at 12:24 AM, Alexander Ivchenko wrote:
>> Config/linux-android.h is a better place for this declaration.
I was wrong here. Config/linux-android.h is not a "re-includable" header, and
is not fit for function declarations.
>
> That wouldn't help, I got the following error:
>
> In file included from ../../.././gcc/tm.h:24:0,
> from [..]/src/gcc/libgcc/generic-morestack-thread.c:29:
> [..]/src/gcc/libgcc/../gcc/config/linux-android.h:62:1: error: unknown
> type name ‘bool’
> extern bool linux_android_has_ifunc_p (void);
> ^
>
> Anyway, linux-protos.h looks to me as a good thing to have (e.g. for
> libc_has_function hook, that is
> supposed to be commited in a near future) for declaring linux (and
> Android) specific versions of hooks..
OK, I agree. In theory linux_android_has_ifunc_p could've been placed into
linux-android-protos.h, but having a separate file (from linux-protos.h) just
for 1-2 declarations is not justified.
>>> + "It returns true if the target supports GNU indirect functions.\n\
>>> +The support includes the assembler, linker and dynamic linker.\n\
>>> +The default value of this hook is defined as for the host machine.",
>>
>> Are your sure the last sentence is correct? It seems the default value for
>> this hook is based on which libc is being used. Maybe it would be more
>> accurate to say "The default value of this hook is based on target's libc."?
>
> Well yes, you are right that the default value depends on version of
> libc, but this version
> is checked on the configure time for the host machine
> (HAVE_GNU_INDIRECT_FUNCTION),
No. And even if that was the case that would be a bug.
HAVE_GNU_INDIRECT_FUNCTION is set based on default_gnu_indirect_function
variable defined in config.gcc (unless overridden with a configure argument).
This variable is set to true for targets that support IFUNCs irrespective of
host and host's libc.
> --- a/gcc/config.gcc
> +++ b/gcc/config.gcc
> @@ -637,6 +637,11 @@ case ${target} in
> native_system_header_dir=/include
> ;;
> esac
> + case $target in
> + *linux*)
> + tm_p_file="${tm_p_file} linux-protos.h"
> + ;;
> + esac
> # glibc / uclibc / bionic switch.
> # uclibc and bionic aren't usable for GNU/Hurd and neither for GNU/k*BSD.
> case $target in
> @@ -662,8 +667,10 @@ case ${target} in
> # Add Android userspace support to Linux targets.
> case $target in
> *linux*)
> + tmake_file="${tmake_file} t-linux-android"
> tm_file="$tm_file linux-android.h"
> extra_options="$extra_options linux-android.opt"
> + extra_objs="$extra_objs linux-android.o"
> ;;
> esac
> # Enable compilation for Android by default for *android* targets.
>
Also scan config.gcc for any other occurences of linux-android.h and add same
changes there. I believe only arm*-*-linux-* is affected.
> --- a/gcc/config/host-linux.c
> +++ b/gcc/config/host-linux.c
> @@ -23,7 +23,6 @@
> #include "hosthooks.h"
> #include "hosthooks-def.h"
>
> -
> /* Linux has a feature called exec-shield-randomize that perturbs the
> address of non-fixed mapped segments by a (relatively) small amount.
> The feature is intended to make it harder to attack the system with
Don't change formatting unless you are editing the code around it.
> diff --git a/gcc/config/linux-android.c b/gcc/config/linux-android.c
> new file mode 100644
> index 0000000..47cc50a
> --- /dev/null
> +++ b/gcc/config/linux-android.c
...
> +You should have received a copy of the GNU General Public License
> +along with GCC; see the file COPYING3. If not see
> +<http://www.gnu.org/licenses/>. */
> +
> +#include "config.h"
> +#include "system.h"
> +#include "coretypes.h"
> +#include "tm.h"
Add '#include "linux-protos.h"'. Remember to update t-linux-android.
> +
> +/* Android does not support GNU indirect functions. */
> +
> +bool
> +linux_android_has_ifunc_p (void)
> +{
> + return TARGET_ANDROID ? false : HAVE_GNU_INDIRECT_FUNCTION;
> +}
>
Please send one last version for the final review, primarily to double check
your changes to arm*-linux-* to avoid breaking it.
Thanks!
--
Maxim Kuvyrkov
