S390: Always enable static PIE if build with lld.
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Commit Message
LLVM ld.lld now also supports s390x and avoids unnecessary TPOFF
relocations for position independent executables. Both recent
commits were also cherry-picked to LLVM 18.
This patch just enables static PIE if build with lld.
---
sysdeps/s390/s390-64/configure | 10 ++++++++--
sysdeps/s390/s390-64/configure.ac | 10 ++++++++--
2 files changed, 16 insertions(+), 4 deletions(-)
Comments
On 19/02/24 12:49, Stefan Liebler wrote:
> LLVM ld.lld now also supports s390x and avoids unnecessary TPOFF
> relocations for position independent executables. Both recent
> commits were also cherry-picked to LLVM 18.
What about old lld that does not have the cherry-picked commits? Should
we follow other practice and check this with a proper test instead?
>
> This patch just enables static PIE if build with lld.
> ---
> sysdeps/s390/s390-64/configure | 10 ++++++++--
> sysdeps/s390/s390-64/configure.ac | 10 ++++++++--
> 2 files changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/sysdeps/s390/s390-64/configure b/sysdeps/s390/s390-64/configure
> index 824ae9c129..c26785f32f 100644
> --- a/sysdeps/s390/s390-64/configure
> +++ b/sysdeps/s390/s390-64/configure
> @@ -12,8 +12,14 @@ case $($LD --version) in
> libc_cv_s390x_staticpie_req_version=no
> ;;
> "LLD"*)
> - # As of 2023-08-07, there is no lld which supports s390x.
> - libc_cv_s390x_staticpie_req_version=no
> + # The required lld patches are available with LLVM 18:
> + # - [lld] Add target support for SystemZ (s390x) #75643
> + # https://github.com/llvm/llvm-project/pull/75643
> + # 2024-02-13: https://github.com/llvm/llvm-project/commit/fe3406e349884e4ef61480dd0607f1e237102c74
> + # - [lld/ELF] Avoid unnecessary TPOFF relocations in GOT for -pie #81739
> + # https://github.com/llvm/llvm-project/pull/81739
> + # 2024-02-14: https://github.com/llvm/llvm-project/commit/6f907733e65d24edad65f763fb14402464bd578b
> + libc_cv_s390x_staticpie_req_version=yes
> ;;
> *)
> # The required binutils patches are available with bintuils 2.39
> diff --git a/sysdeps/s390/s390-64/configure.ac b/sysdeps/s390/s390-64/configure.ac
> index 4657de0d37..2b5bffc107 100644
> --- a/sysdeps/s390/s390-64/configure.ac
> +++ b/sysdeps/s390/s390-64/configure.ac
> @@ -12,8 +12,14 @@ case $($LD --version) in
> libc_cv_s390x_staticpie_req_version=no
> ;;
> "LLD"*)
> - # As of 2023-08-07, there is no lld which supports s390x.
> - libc_cv_s390x_staticpie_req_version=no
> + # The required lld patches are available with LLVM 18:
> + # - [lld] Add target support for SystemZ (s390x) #75643
> + # https://github.com/llvm/llvm-project/pull/75643
> + # 2024-02-13: https://github.com/llvm/llvm-project/commit/fe3406e349884e4ef61480dd0607f1e237102c74
> + # - [lld/ELF] Avoid unnecessary TPOFF relocations in GOT for -pie #81739
> + # https://github.com/llvm/llvm-project/pull/81739
> + # 2024-02-14: https://github.com/llvm/llvm-project/commit/6f907733e65d24edad65f763fb14402464bd578b
> + libc_cv_s390x_staticpie_req_version=yes
> ;;
> *)
> # The required binutils patches are available with bintuils 2.39
On 20.02.24 15:49, Adhemerval Zanella Netto wrote:
>
>
> On 19/02/24 12:49, Stefan Liebler wrote:
>> LLVM ld.lld now also supports s390x and avoids unnecessary TPOFF
>> relocations for position independent executables. Both recent
>> commits were also cherry-picked to LLVM 18.
>
> What about old lld that does not have the cherry-picked commits? Should
> we follow other practice and check this with a proper test instead?
In case of s390x, older lld also do not support s390x at all and the
common link-configure tests will fail.
If you fear that somebody might backport the s390-lld-support patch
without the TPOFF patch, e.g. ldconfig is linked as static PIE and will
fail at startup.
But yes, I can just add a version check to lld 18 as known minimum
version. Then if somebody has backported the support to a previous
version, the PIE configure check will detect if both patches were
backported.
On 21.02.24 08:51, Stefan Liebler wrote:
> On 20.02.24 15:49, Adhemerval Zanella Netto wrote:
>>
>>
>> On 19/02/24 12:49, Stefan Liebler wrote:
>>> LLVM ld.lld now also supports s390x and avoids unnecessary TPOFF
>>> relocations for position independent executables. Both recent
>>> commits were also cherry-picked to LLVM 18.
>>
>> What about old lld that does not have the cherry-picked commits? Should
>> we follow other practice and check this with a proper test instead?
> In case of s390x, older lld also do not support s390x at all and the
> common link-configure tests will fail.
>
> If you fear that somebody might backport the s390-lld-support patch
> without the TPOFF patch, e.g. ldconfig is linked as static PIE and will
> fail at startup.
>
> But yes, I can just add a version check to lld 18 as known minimum
> version. Then if somebody has backported the support to a previous
> version, the PIE configure check will detect if both patches were
> backported.
I've just posted v2 with an additional version check:
https://sourceware.org/pipermail/libc-alpha/2024-February/154896.html
One further hint:
If somebody bootstraps the toolchain from scratch, then there are no
crt-files and the linking configure-tests always fail. Thus static PIE
would not be enabled. Therefore there is the additional version check
which checks for known lld version which allows static PIE.
@@ -12,8 +12,14 @@ case $($LD --version) in
libc_cv_s390x_staticpie_req_version=no
;;
"LLD"*)
- # As of 2023-08-07, there is no lld which supports s390x.
- libc_cv_s390x_staticpie_req_version=no
+ # The required lld patches are available with LLVM 18:
+ # - [lld] Add target support for SystemZ (s390x) #75643
+ # https://github.com/llvm/llvm-project/pull/75643
+ # 2024-02-13: https://github.com/llvm/llvm-project/commit/fe3406e349884e4ef61480dd0607f1e237102c74
+ # - [lld/ELF] Avoid unnecessary TPOFF relocations in GOT for -pie #81739
+ # https://github.com/llvm/llvm-project/pull/81739
+ # 2024-02-14: https://github.com/llvm/llvm-project/commit/6f907733e65d24edad65f763fb14402464bd578b
+ libc_cv_s390x_staticpie_req_version=yes
;;
*)
# The required binutils patches are available with bintuils 2.39
@@ -12,8 +12,14 @@ case $($LD --version) in
libc_cv_s390x_staticpie_req_version=no
;;
"LLD"*)
- # As of 2023-08-07, there is no lld which supports s390x.
- libc_cv_s390x_staticpie_req_version=no
+ # The required lld patches are available with LLVM 18:
+ # - [lld] Add target support for SystemZ (s390x) #75643
+ # https://github.com/llvm/llvm-project/pull/75643
+ # 2024-02-13: https://github.com/llvm/llvm-project/commit/fe3406e349884e4ef61480dd0607f1e237102c74
+ # - [lld/ELF] Avoid unnecessary TPOFF relocations in GOT for -pie #81739
+ # https://github.com/llvm/llvm-project/pull/81739
+ # 2024-02-14: https://github.com/llvm/llvm-project/commit/6f907733e65d24edad65f763fb14402464bd578b
+ libc_cv_s390x_staticpie_req_version=yes
;;
*)
# The required binutils patches are available with bintuils 2.39