Re: tesseract: FTBFS on ppc64el with undefined reference to `__parse_hwcap_and_convert_at_platform'

Hello Alexander ,

tesseract fails to build from source on ppc64el due to a link-time 
failure when building libtesseract.la.

On ppc64el, GCC’s libgcc includes float128 IFUNC objects 
(float128-ifunc.o) that reference glibc
hwcap parsing symbols, including: __parse_hwcap_and_convert_at_platform

During the link of libtesseract.la, the link command does not explicitly 
include the required runtime
libraries (libc, libgcc_s), causing the linker to fail with an undefined 
reference.
Other architectures do not expose this issue due to differences in how 
libgcc and glibc interact, or
because the compiler driver implicitly adds the required libraries.

Proposed fix:

Ensure the required runtime libraries are available during link time on 
ppc64el. This Debian-side fix
resolves the issue. In debian/rules



ifeq ($(DEB_HOST_ARCH),ppc64el)
export DEB_LDFLAGS_MAINT_APPEND += -lgcc -lgcc_s -lc
endif


With this change, the package builds successfully on ppc64el.

Could you please review this and let me know if it looks correct?”


Thanks,
Trupti



On 2026-03-03 18:29, Trupti wrote:
> Package: src:tesseract
> Version:  5.5.0-1
> Severity: important
> Tags: ftbfs
> X-Debbugs-Cc: [email protected]
> User: [email protected]
> Usertags: ppc64el
> 
> 
> Dear Maintainer,
> 
> tesseract fails to build from source on ppc64el with below is the 
> error:
> 
> /usr/bin/powerpc64le-linux-gnu-ld.bfd:
> /usr/lib/gcc/powerpc64le-linux-gnu/15/libgcc.a(float128-ifunc.o):(.data+0x0):
> undefined reference to `__parse_hwcap_and_convert_at_platform'
> collect2: error: ld returned 1 exit status
> make[3]: *** [Makefile:3693: libtesseract.la] Error 1
> make[3]: Leaving directory '/build/reproducible-path/tesseract-5.5.0'
> make[2]: *** [Makefile:8022: all-recursive] Error 1
> make[2]: Leaving directory '/build/reproducible-path/tesseract-5.5.0'
> make[1]: *** [debian/rules:22: override_dh_auto_build] Error 2
> make[1]: Leaving directory '/build/reproducible-path/tesseract-5.5.0'
> make: *** [debian/rules:19: binary-arch] Error 2
> dpkg-buildpackage: error: debian/rules binary-arch subprocess failed
> with exit status 2
> 
> 
> This is the build log on ppc64el for reference :
> 
> https://buildd.debian.org/status/fetch.php?pkg=tesseract&arch=ppc64el&ver=5.5.0-1%2Bb3&stamp=1772392220&raw=0
> 
> 
> Thanks,
> Trupti