Ubuntu 18.04 on ARM64: undefined reference to `exp@GLIBC_2.29'

[Benoit Blanchon]

Hi,

I successfully compiled a shared library of PDFium on Ubuntu 20.04 with "target_cpu" set to either "x86", "x64", "arm", or "arm64"

(see https://github.com/bblanchon/pdfium-binaries)

However, if I try to do the same with Ubuntu 18.04, all targets build, except "arm64".

The link step fails with the following errors:

libpdfium.so: undefined reference to `exp@GLIBC_2.29'
libpdfium.so: undefined reference to `log@GLIBC_2.29'
libpdfium.so: undefined reference to `pow@GLIBC_2.29'

I investigated the problem and reported my conclusions here:

https://github.com/bblanchon/pdfium-binaries/issues/82#issuecomment-1160190986

In short, "reversion_glibc.py", the script that changes the required glibc version in the sysroot, is skipped for arm64. The comment says "Glibc is compiled in a way where many libm math functions do not have compatibility symbols for versions <= 2.17."

I'm still looking for a solution.

Please let me know if you can help.

Best regards,

Benoit Blanchon

[Lei Zhang]

Since you are looking at //build code in the Chromium source repo, you
may want to ask on a Chromium mailing list. Likely if you build a
Chromium build target with the same build config, it will have the
same issue.

> --
> You received this message because you are subscribed to the Google Groups "pdfium" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to pdfium+un...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/pdfium/8d57a052-7500-40a4-84b5-7b2b1db6c9c5n%40googlegroups.com.

[Benoit Blanchon]

Thanks for the response, Lei.

I did as you suggested and opened a discussion on Chromium's mailing list:

https://groups.google.com/a/chromium.org/g/chromium-dev/c/SdCs9k3celo/m/TMJqiKYaBQAJ