Dovecot 2.2.30* compiling error

[Andrey Jr. Melnikov]

Mart Pirita <sysadmin at e-positive.ee> wrote:
> Hello.

> I cant build 2.2.30*, but I can build fine version 2.2.29* with same
> options:

> RedHat based customized distro, 2.6.28.10 kernel

[...]

> Build error:

> ltest_lib-test-bits.o: In function `bits_required64':
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/bits.h:33: undefined
> reference to `__builtin_clzll'
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/bits.h:33: undefined
> reference to `__builtin_clzll'
> test_lib-test-bits.o: In function `test_bits_requiredXX':
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/test-bits.c:74: undefined
> reference to `__builtin_clzll'
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/test-bits.c:74: undefined
> reference to `__builtin_clzll'
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/test-bits.c:74: undefined
> reference to `__builtin_clzll'
> ./.libs/liblib.a(numpack.o): In function `numpack_decode':
> /usr/src/redhat/BUILD/dovecot-2.2.30/src/lib/numpack.c:43: undefined
> reference to `__builtin_clz'
> collect2: ld returned 1 exit status


> Please advise?
Time to upgrade ancient GCC?