Cross-building ffmpeg with static gnutls for android fails at configure step

[Maxime Gauduin]

Greetings,

I'm trying to cross-compile ffmpeg 3.4.1 for android using a freshly generated x86_64 android toolchain at API version 21.

Every external library was built static so the resulting ffmpeg binary links to the least possible number of libs.

Everything works fine except configure can't find gnutls with undefined references to a lot of GMP symbols despite -lgmp having been added to LIBS.

Here's my config.log: ​https://paste.xinu.at/Qxb/

[Carl Eugen Hoyos]

Is the issue reproducible with current FFmpeg git head?
Please attach all necessary log files here in the ticket, do not use external resources (except for large media files).

How did you compile gmp?

[Maxime Gauduin]

config.log

[Maxime Gauduin]

Reproduced with armv7 and aarch64, I've attached the config.log here this time.

Here is an overview of how I'm building gmp:

./configure --host=aarch64-linux-android --prefix=/srv/buildbot/aarch64_android/libgmp-aarch64_android/staging --disable-shared --enable-static

environment:

CC=aarch64-linux-android-clang
CFLAGS=-march=armv8-a -Os -pipe -fPIE -I/srv/buildbot/aarch64_android/staging/include
CHOST=aarch64-linux-android
CPPFLAGS=-D_FORTIFY_SOURCE=2 -I/srv/buildbot/aarch64_android/staging/include
CXX=aarch64-linux-android-clang++
CXXFLAGS=-march=armv8-a -Os -pipe -fPIE -I/srv/buildbot/aarch64_android/staging/include
LANG=en_US.utf8
LANGUAGE=C
LC_ALL=C
LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now -pie -static-libstdc++ -L/srv/buildbot/aarch64_android/staging/lib
PATH=/srv/buildbot/aarch64_android/toolchain/bin:/srv/buildbot/aarch64_android/staging/bin:/srv/buildbot/aarch64_android/staging/sbin:/usr/local/sbin:/usr/local/bin:/usr/bin
PKG_CONFIG_PATH=/srv/buildbot/aarch64_android/staging/lib/pkgconfig

FYI, I've been successfully cross-building a dynamically linked ffmpeg with the same gmp (albeit with --disable-static and --enable-shared) for linux platforms with all those architectures using toolchains from linaro or generated with crosstool-ng. The only thing that doesn't work when I'm going static is gnutls.

I'll try the git head as soon as I can.

[Maxime Gauduin]

I can reproduce using the current git head as well.

[Maxime Gauduin]

Hi guys, do you have any pointer that would help me diagnose the issue?

[Maxime Gauduin]

Turns out order matters, -lgmp needs to come after -lnettle and -lhogweed.