Bio::ToolBox - MacOS Notes

MacOS Notes

While Macs have a Unix-compatible command-line environment (Darwin), there are a few issues and solutions that I have encountered that may be useful to someone. Some of these pertain to older OS X releases (and left here for posterity), but some, such as rpath, are still relevant to current macOS releases.

Install XCode command line tools

You don’t need the full blown XCode installed, just the command line tools. Running the following command in terminal will prompt to install them. You will need administrator permissions.

$ xcode-select --install

Installing your own Perl

Apple is generally a little slow in updating their Perl compared to the latest available versions, and it is compiled for multiple architectures with backwards compatibility with 32-bit i386 processors (!), at least as of High Sierra (10.13). Some of the errors below will go away if you compile your own Perl, but your success may vary.

On Mojave (10.14), the system Perl appears to be ~~broken~~ fixed as of 10.14.3 with regards to compiling XS modules.

For installing your own Perl, the easiest route is to use either Homebrew or PerlBrew.

Be sure to use a recent version of PerlBrew. Older versions sometimes fails to set the minimum MacOS version. In such cases, I have found the recommendations described here to be helpful.

Linking errors

When linking Perl modules with XS code (compiled C extensions), especially when using the system Perl, you may see the following errors.

ld: warning: object file was built for newer OSX version (10.13) than being linked (10.4)

This is due to Apple compiling their system Perl with far-reaching backwards compatibility; the Perl binary was compiled for both i386 and x86_64, but in all likelihood your XS was compiled only for x86_64. In some cases, this is a harmless error; in other cases, it’s a deal breaker. The best solution is to install your own Perl.

rpath errors

This is especially notable with the Bio::DB::Big installation as described above, where the ./Build test fails dramatically because a shared library can not be loaded by the bundle, usually with an error message including this:

Reason: unsafe use of relative rpath libBigWig.so in blib/arch/auto/Bio/DB/Big/Big.bundle with restricted binary

The solution is to manually re-link the bundle to the shared library file with the following command. See this link for the source of the solution.

$ install_name_tool -change libBigWig.so /path/to/lib/libBigWig.so blib/arch/auto/Bio/DB/Big/Big.bundle

DB_File errors

There are reports of issues regarding certain BioPerl modules that rely on the Berkley database module DB_File. This appears to stem from an issue with the Apple-supplied library in High Sierra (10.13) as described here. The best solution is to install your own berkley-db library.

This issue is not evident on the newer Mojave (10.14) and subsequent releases.

For BioToolBox users, the biggest effect appears to be exceptionally long times during Build tests, specifically file 04.DB.t that uses the in-memory database adapater (maybe 20-30 seconds instead of 1), and excruciatingly long Bio::DB::SeqFeature::Store database builds (possibly days or weeks, I give up).

Set::IntervalTree failures

Installing Set::IntervalTree may lead failures. This isn’t necessarily an issue with per se, but rather one of its dependencies, ExtUtils::CppGuess, which fails to install on recent versions of macOS. In fact, most tests of it on Darwin fail. Fortunately, the failing tests don’t appear to be essential for installing Set::IntervalTree, so force install ExtUtils::CppGuess and try re-installing Set::IntervalTree again – it will probably work.

libBigWig

When manually installing libBigWig on recent versions of macOS (observed with Sonoma, 14.x and libBigWig v0.4.7), the compilation may fail at first. To check for libCurl dependencies, it attempts to compile a small test program and runs the command mktemp --suffix=.c. While that --suffix option is available to versions on Linux platforms, it is not available to the version on macOS, thus breaking the detection of libCurl. To work around this, we just have to tell it that, yes, we have libCurl. Edit the Makefile and comment out the five lines after # Create a simple test-program... and add a new line

HAVE_CURL=YES

Then re-run make and it should compile ok with curl support.

However, it’s not over yet. If you run make test, the test/testRemote test seems to fail. This appears to be an innocuous platform-specific error. If you proceed to compile the Bio::DB::Big Perl module, it appears to work ok with remote files during its testing, albeit through a fake remote test with Test::Fake::HTTPD (if it’s installed). However, empirical testing with real remote data (via https) seems to work ok.