Using llvm-config [version=10.0.0]
g++ -c -Os -fomit-frame-pointer  -o src/llvm/ext/llvm_ext.o src/llvm/ext/llvm_ext.cc -I/usr/lib/llvm10/include -std=c++14   -fno-exceptions -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
gcc -Os -fomit-frame-pointer -fPIC  -Os -fomit-frame-pointer  -c -o src/ext/sigfault.o src/ext/sigfault.c
ar -rcs src/ext/libcrystal.a src/ext/sigfault.o
CRYSTAL_CONFIG_LIBRARY_PATH="" CRYSTAL_CONFIG_BUILD_COMMIT="3b715c5871" SOURCE_DATE_EPOCH="1592321389" ./bin/crystal build --verbose --target aarch64-alpine-linux-musl  --release --progress --threads 8 --link-flags="-Wl,--as-needed"  -o .build/crystal src/compiler/crystal.cr -D without_openssl -D without_zlib
Invalid memory access (signal 11) at address 0xfff24c337088
[0xca7fb4] ???
[0xc12de8] ???
[0x18c556c] ???
[0x15545fc] ???
[0xcf5e8c] ???
[0x15548e0] ???
[0x1751368] ???
[0x1705908] ???
[0x96dff4] ???
[0x8dc388] ???
[0xc25954] ???
[0xc15e50] ???
[0x435790] ???
[0x18ae6c4] ???
make: *** [Makefile:121: .build/crystal] Error 11
>>> ERROR: crystal: build failed