bpo-38634: Allow non-apple build to cope with libedit by serge-sans-paille · Pull Request #16986 · python/cpython

@serge-sans-paille

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.

https://bugs.python.org/issue38634

@serge-sans-paille

@ned-deily

Thanks for this PR. There is a long standing open issue (bpo-13501) to generalize libedit support in Python including a PR (#12076) that is more involved than just removing the APPLE conditional code as proposed here. libedit itself has changed over the years so perhaps not all of the changes in #12076 need to be made. But we should probably start from there. Assigning to @gpshead who last looked at bpo-13501.

labath

vstinner

vstinner

@serge-sans-paille

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.

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@miss-islington

@miss-islington

@miss-islington

Sorry @serge-sans-paille and @vstinner, I had trouble checking out the 3.7 backport branch.
Please backport using cherry_picker on command line.
cherry_picker 7105319ada2e663659020cbe9fdf7ff38f421ab2 3.7

miss-islington added a commit to miss-islington/cpython that referenced this issue

Dec 4, 2019
The readline module now detects if Python is linked to libedit at runtime
on all platforms.  Previously, the check was only done on macOS.

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.
(cherry picked from commit 7105319)

Co-authored-by: serge-sans-paille <serge.guelton@telecom-bretagne.eu>

@bedevere-bot

@vstinner

I did the 3.8 since it was possible to automate it. I'm not interested to backport it to 3.7, since it's too much effort for a rare use case.

miss-islington added a commit that referenced this issue

Dec 4, 2019
The readline module now detects if Python is linked to libedit at runtime
on all platforms.  Previously, the check was only done on macOS.

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.
(cherry picked from commit 7105319)

Co-authored-by: serge-sans-paille <serge.guelton@telecom-bretagne.eu>

sthagen added a commit to sthagen/python-cpython that referenced this issue

Dec 4, 2019
 bpo-38634: Allow non-apple build to cope with libedit (pythonGH-16986)

jacobneiltaylor added a commit to jacobneiltaylor/cpython that referenced this issue

Dec 5, 2019
The readline module now detects if Python is linked to libedit at runtime
on all platforms.  Previously, the check was only done on macOS.

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.

shihai1991 added a commit to shihai1991/cpython that referenced this issue

Jan 31, 2020
The readline module now detects if Python is linked to libedit at runtime
on all platforms.  Previously, the check was only done on macOS.

If Python is used as a library by a binary linking to libedit, the linker
resolves the rl_initialize symbol required by the readline module against
libedit instead of libreadline, which leads to a segfault.

Take advantage of the existing supporting code to have readline module being
compatible with both situations.

rohieb added a commit to rohieb/cpython that referenced this issue

Jan 10, 2021
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:

  --with-readline           link against libreadline (the default)
  --with-readline=editline  link against libeditline
  --with-readline=no        disable building the readline module
  --without-readline        (same)

The runtime detection of libedit vs. readline was already done in commit
7105319 (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (pythonGH-16986)").

Fixes: pythonGH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)

rohieb added a commit to rohieb/cpython that referenced this issue

Jan 28, 2021
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:

  --with-readline           link against libreadline (the default)
  --with-readline=editline  link against libeditline
  --with-readline=no        disable building the readline module
  --without-readline        (same)

The runtime detection of libedit vs. readline was already done in commit
7105319 (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (pythonGH-16986)").

Fixes: pythonGH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)

gpshead pushed a commit that referenced this issue

Feb 9, 2021
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:

  --with-readline           link against libreadline (the default)
  --with-readline=editline  link against libeditline
  --with-readline=no        disable building the readline module
  --without-readline        (same)

The runtime detection of libedit vs. readline was already done in commit
7105319 (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (GH-16986)").

Fixes: GH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)

adorilson added a commit to adorilson/cpython that referenced this issue

Mar 13, 2021
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:

  --with-readline           link against libreadline (the default)
  --with-readline=editline  link against libeditline
  --with-readline=no        disable building the readline module
  --without-readline        (same)

The runtime detection of libedit vs. readline was already done in commit
7105319 (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (pythonGH-16986)").

Fixes: pythonGH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)

tnir added a commit to tnir/cpython that referenced this issue

Apr 15, 2021
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:

  --with-readline           link against libreadline (the default)
  --with-readline=editline  link against libeditline
  --with-readline=no        disable building the readline module
  --without-readline        (same)

The runtime detection of libedit vs. readline was already done in commit
7105319 (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (pythonGH-16986)").

Fixes: pythonGH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)

@tnir tnir mentioned this pull request

Apr 15, 2021