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Using the GNU ld Linker on Solaris

March 25th, 2011

On Solaris, GCC by default is compiled with the option –with-ld=/usr/ccs/bin/ld, telling it to use the Solaris linker. Unfortunately GCC uses this value above all else, meaning it will ignore LD= environment variables to set an alternative linker, such as /usr/sfw/bin/gld

Although tools like libtool/autoconf will pick up your LD= environment variable, and detect which options the linker supports (and whether its GNU ld or not), libtool unfortunately still calls gcc for the linking stage, which then ignores LD=. This makes it near-impossible to use GNU ld without actually doing a nasty hack, like “mv /usr/ccs/bin/ld /usr/ccs/bin/ld.off ; ln -s /usr/sfw/bin/ld /usr/ccs/bin/ld”. Yuck!

However, today when trying to get lame to compile using nasm (which generates objects that refuse to link with Solaris LD), I found Solaris LD accepts a very useful environment variable. The variable is LD_ALTEXEC.

Solaris LD will actually re-exec the value of LD_ALTEXEC, meaning that if you set LD_ALTEXEC to /usr/sfw/bin/gld, when /usr/ccs/bin/ld gets called, it immediately instead calls /usr/sfw/bin/gld with the arguments passed on. Thus, you can use whatever linker you wish. Hurrah! :-)

Entry Filed under: General