how to turn docbuild off with conda

[Martin R]

Dear all,

Using the "classical" install, I can do "configure --disable-doc" so docs are not build and recompilation is reasonably fast.

How can I do this in a conda install.  When I start sage, it tells me

../../src/doc/meson.build:5: WARNING: Documentation building enabled, generating targets may be slow. To disable this, pass -Dbuild-docs=false. 

but I do not understand how I can pass this option.  I tried

(sage-dev) martin@toolbox:~/sage-trac$ meson configure -Dbuild-docs=False

ERROR: No valid build directory found, cannot modify options.

Best wishes,

Martin

[Antonio Rojas]

meson setup your-build-dir -Dbuild-docs=False

[Martin R]

:-(  this did not work.

I'm not completely sure what my your-build-dir is, I was guessing "build" in the root dir of my sage.  Or is it

 meson-python: building sagemath: /home/martin/miniforge3/envs/sage-dev/bin/ninja

?

[Dima Pasechnik]

Replace "your-build-dir" by something like "build/sagenodoc"

[Tobia...@gmx.de]

You simply use pip to install sage, right?

In this case,  `pip install <other args> -Csetup-args=" -Dbuild-docs=False" .` should work.

[Martin R]

I did not install sage myself - Julian did it for me on sagedays.  It looked easy back then (in January 2026), but I do not have any recollection of the details.  Some apps are asking me for my password once a month lest I forget, maybe I should reinstall sage from scratch once a month, too :-)

@Dima: I tried.  This creates a new directory build/sagenodoc.  However, doing "./sage" then wants to build the docs again.

@Tobias: how can I find out what <other args> were, assuming that it was a pip install? 

Martin

[Tobia...@gmx.de]

See https://doc.sagemath.org/html/en/installation/source.html#using-conda, so in summary:

pip install --no-build-isolation --editable -Csetup-args="-Dbuild-docs=False" .

[Martin R]

This gives me

(sage-dev) martin@toolbox:~/sage-trac$ pip install --no-build-isolation --editable -Csetup-args="-Dbuild-docs=False" .
ERROR: -Csetup-args=-Dbuild-docs=False is not a valid editable requirement. It should either be a path to a local project or a VCS URL (beginning with bzr+ht
tp, bzr+https, bzr+ssh, bzr+sftp, bzr+ftp, bzr+lp, bzr+file, git+http, git+https, git+ssh, git+git, git+file, hg+file, hg+http, hg+https, hg+ssh, hg+static-h
ttp, svn+ssh, svn+http, svn+https, svn+svn, svn+file).

[Tobia...@gmx.de]

Sorry, the other way around:

pip install -Csetup-args="-Dbuild-docs=False" --no-build-isolation --editable .

(I'm not at my development machine, so cannot test)

[Martin R]

Cool, this worked essentially!

Essentially, because apparently this command turned off another option that controlled output what meson is doing - i.e., recompiling stuff.

https://doc.sagemath.org/html/en/installation/source.html says that I should pass "--verbose" to pip install, but apparently this controls the verbosity of pip, not of meson.

Martin

[Tobia...@gmx.de]

You also need to pass  -Ceditable-verbose=true

If you have the time, could you please create a PR that adds a short description of those two options to the documentation? Thanks in advance!

[Martin R]

https://github.com/sagemath/sage/pull/42131

(draft, because I have to double check at home whether the instruction is correct)

Martin

[Tobia...@gmx.de]

Thanks!

[Vincent Macri]

On a similar topic, how do you turn ccache ON with conda?

[Tobia...@gmx.de]

I think 

            export CC="ccache $CC"

            export CXX="ccache $CXX"

should do the trick.

[Vincent Macri]

Have you tested this and had it work for you? Because it doesn't seem to be working for me. Re-compilations are still slow and my task manager does not show the ccache program running. The autogenerated file in build/cp314/build.ninja seems to hardcode paths to compilers rather than use the environment variables CC and CXX.

[Tobia...@gmx.de]

CI uses it (https://github.com/sagemath/sage/actions/runs/26661566510/workflow#L134-L136), and the cache there seems to work: https://github.com/sagemath/sage/actions/runs/26661566510/job/78585116714#step:36:4

Meson should print something in the log like: 
C compiler for the host machine: /usr/bin/ccache /usr/share/miniconda/envs/sage-dev/bin/x86_64-conda-linux-gnu-cc (gcc 14.3.0 "x86_64-conda-linux-gnu-cc (conda-forge gcc 14.3.0-18) 14.3.0")

[Dima Pasechnik]

meson does support settings CC and CXX, according to
<https://mesonbuild.com/Reference-tables.html#compiler-and-linker-selection-variables>

Ninja files need to be regenerated, with the values of CC/CXX hardcoded. So you don't need to actually do the build to test this, just to look in the ninja file.