I could not find the solution to this problem on the internet, therefore I post it here, while it is unrelated to XyGrib (and in the wrong language, excusez moi).
If you run into this problem, you'll have to build libnova from source on Ubuntu 18.04 for arm64.
Something like (using root, fakeroot or another method):
apt-get --compile source libnova-0.16-0
dpkg -i libnova-dev-0.16-2_arm64.deb
This solves the "-fPIC" problem, the XyGrib compilation can be finished and you can proceed with installation.
Pytheas wrote: Bon, maintenant une erreur dans le link
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[100%] Linking CXX executable XyGrib
< remove unnecessary parts >
/usr/bin/ld: /usr/lib/gcc/aarch64-linux-gnu/7/../../../aarch64-linux-gnu/libnova.a(julian_day.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `__stack_chk_guard@@GLIBC_2.17' which may bind externally can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: /usr/lib/gcc/aarch64-linux-gnu/7/../../../aarch64-linux-gnu/libnova.a(julian_day.o)(.text+0x4): unresolvable R_AARCH64_ADR_PREL_PG_HI21 relocation against symbol `__stack_chk_guard@@GLIBC_2.17'
/usr/bin/ld: final link failed: Bad value
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