Bug 202333 – Check values of variables before extracting index in perl

• Status: RESOLVED
• Resolution: FIXED
• Component: New Bugs

[Paulo Matos]

Check values of variables before extracting index in perl

[Paulo Matos]

Created attachment 379766 [details]
Patch

[Paulo Matos]

The problem here is that some gcc versions do not have target or host variables set when built. An example, is gcc-8 from Arch Linux, whose version shows:
$ gcc-8 -v
Using built-in specs.
COLLECT_GCC=gcc-8
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/8.3.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc8/src/gcc/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,fortran,lto --enable-shared --enable-threads=posix --enable-libmpx --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --disable-multilib --disable-werror --enable-checking=release --enable-default-pie --enable-default-ssp --enable-cet=auto --program-suffix=-8 --enable-version-specific-runtime-libs
Thread model: posix
gcc version 8.3.0 (GCC)

This was causing a warning in the perl script because @target[0] and @host[0] are not defined if the regexp fails to match.

I noticed the warning while doing:
CC=gcc-8 CXX=g++-8 Tools/Scripts/build-jsc --jsc-only --debug

[Alexey Proskuryakov]

Comment on attachment 379766 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=379766&action=review

> Tools/Scripts/webkitdirs.pm:1393
> +        if (!@target || !@host) {

This seems worth explaining in a comment. It’s not even clear from bug comments why this situation implies cross-compilation, and it will be even more mysterious without the context.

[Paulo Matos]

Created attachment 381190 [details]
Patch

[Paulo Matos]

(In reply to Alexey Proskuryakov from comment #3)
> Comment on attachment 379766 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=379766&action=review
> 
> > Tools/Scripts/webkitdirs.pm:1393
> > +        if (!@target || !@host) {
> 
> This seems worth explaining in a comment. It’s not even clear from bug
> comments why this situation implies cross-compilation, and it will be even
> more mysterious without the context.

Apologies for the delay on this. You are correct that we should not assume cross-compilation, if there's no information about host or target on the compiler version information we assume no cross-compilation. Have now uploaded new patch.

[WebKit Commit Bot]

Comment on attachment 381190 [details]
Patch

Clearing flags on attachment: 381190

Committed r251234: <https://trac.webkit.org/changeset/251234>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/56370686>