Bug 194147 – [CMake] Build 32bit binaries on Linux/64bit when the --32-bit is passed to build-jsc

• Component: Tools / Tests
• Status: RESOLVED FIXED

[Xan Lopez]

The infrastructure to easily build 32bit binaries in a 64bit host is almost there. The following patch fixes a few issues in the build script that allow us to do this transparently.

[Xan Lopez]

Created attachment 360851 [details]
Make --32-bit flag in build-jsc work in Linux/64bit

[Xan Lopez]

Adding a few more eyes here with relevant reviews in the file.

[Daniel Bates]

Comment on attachment 360851 [details]
Make --32-bit flag in build-jsc work in Linux/64bit

View in context: https://bugs.webkit.org/attachment.cgi?id=360851&action=review

> CMakeLists.txt:96
> +    if (FORCE_32BIT)

Ok as-is. Just a thought, add a comment to explain like what you did in the change log that this is a workaround/hack to support building 32 bit without having to formulate the build  as a crosscompile

> Tools/Scripts/webkitdirs.pm:2264
> +    if ($architecture eq "x86_64"  && shouldBuild32Bit()) {

Looks like an extra space character before the &&

> Tools/Scripts/webkitdirs.pm:2266
> +        # files in debian-based systems, for the others

Debian

> Tools/Scripts/webkitdirs.pm:2269
> +        push @cmakeArgs, '-DFORCE_32BIT=ON -DCMAKE_PREFIX_PATH="/usr" -DCMAKE_LIBRARY_ARCHITECTURE=x86';

Doesn't prefix path affect install path? If so, is that what we want? I don't understand the prefix path part.

> Tools/Scripts/webkitdirs.pm:2270
> +        $ENV{'CFLAGS'} = "-m32" . ($ENV{'CFLAGS'} || "");

More " please and less ' but only on this line and the below. The above line is perfect.

> Tools/Scripts/webkitdirs.pm:2271
> +        $ENV{'CXXFLAGS'} = "-m32" . ($ENV{'CXXFLAGS'} || "");

Ditto.

[Xan Lopez]

(In reply to Daniel Bates from comment #3)
> > +        push @cmakeArgs, '-DFORCE_32BIT=ON -DCMAKE_PREFIX_PATH="/usr" -DCMAKE_LIBRARY_ARCHITECTURE=x86';
> 
> Doesn't prefix path affect install path? If so, is that what we want? I
> don't understand the prefix path part.
> 

Hrm, that would be CMAKE_INSTALL_PREFIX I guess? My understanding is that it is used by the FIND_XXX commands (see https://cmake.org/cmake/help/v3.0/variable/CMAKE_PREFIX_PATH.html). If it is set (it's empty by default) CMake search the .pc files in CMAKE_PREFIX_PATH + "/lib", which is the right path for 32bit .pc files. Otherwise, in a 64bit system, it would use /usr/lib64, etc.

(That does not apply to Debian, that's why I also set another variable as indicated in the comment).

[Xan Lopez]

Created attachment 364259 [details]
JSC --32-bit build/intel

Patch addressing review comments.

[Michael Saboff]

Comment on attachment 364259 [details]
JSC --32-bit build/intel

rs=me

[WebKit Commit Bot]

Comment on attachment 364259 [details]
JSC --32-bit build/intel

Clearing flags on attachment: 364259

Committed r242724: <https://trac.webkit.org/changeset/242724>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/48776468>

[Michael Catanzaro]

Please fix this:

Use of uninitialized value $architecture in string eq at /home/mcatanzaro/Projects/WebKit/Tools/Scripts/webkitdirs.pm line 2265.

[Alberto Garcia]

*** Bug 191944 has been marked as a duplicate of this bug. ***