Alpine linux can't link to the library installed via `apk`

[wisonye]

1. Install via native apk

   doas apk --no-cache add notcurses notcurses-dev notcurses-doc notcurses-libs notcurses-static notcurses-tetris notcurses-view

2. Create a hello program, compile and run:

   >>> [ RUN ]
   >>> OS_TYPE: Linux
   >>> BUILD_TYPE: Debug
   >>> STATIC_BUILD: No
   >>> MUSL_LIBC: Yes
   >>> COMMAND: /usr/lib/llvm19/bin/clang
   -std=c23 -Wall -Werror
   -D ENABLE_DEBUG_LOG
   -D_BSD_SOURCE -DNCURSES_WIDECHAR
   -lnotcurses -lnotcurses-core
   -D __MUSL__ -D _GNU_SOURCE
   -g
   -o ./temp_build/main
   src/main.c
   && ./temp_build/main
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /tmp/main-9b2484.o: in function `main':
   # /home/wison/c/notcurses-tutorial/c/src/main.c:95:(.text+0x4c): undefined reference to `notcurses_core_init'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /home/wison/c/notcurses-tutorial/c/src/main.c:96:(.text+0x59): undefined reference to `notcurses_stdplane'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /home/wison/c/notcurses-tutorial/c/src/main.c:105:(.text+0xcb): undefined reference to `notcurses_stop'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /tmp/main-9b2484.o: in function `ncplane_putstr_yx':
   # /usr/include/notcurses/notcurses.h:2277:(.text+0x136): undefined reference to `ncplane_putegc_yx'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /tmp/main-9b2484.o: in function `notcurses_render':
   # /usr/include/notcurses/notcurses.h:1150:(.text+0x1c1): undefined reference to `notcurses_stdplane'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /usr/include/notcurses/notcurses.h:1151:(.text+0x1ce): undefined reference to `ncpile_render'
   # /usr/lib/gcc/x86_64-alpine-linux-musl/14.2.0/../../../../x86_64-alpine-linux-musl/bin/ld: /usr/include/notcurses/notcurses.h:1154:(.text+0x1e5): undefined reference to `ncpile_rasterize'
   # clang: error: linker command failed with exit code 1 (use -v to see invocation)

   Libraries in the default link path:

   ls -lht /usr/lib/{libnotcurses.so, libnotcurses-core.so}
   
   # lrwxrwxrwx    1 root     root          22 Mar 12 16:04 /usr/lib/libnotcurses-core.so -> libnotcurses-core.so.3*
   # lrwxrwxrwx    1 root     root          17 Mar 12 16:04 /usr/lib/libnotcurses.so -> libnotcurses.so.3*

[dankamongmen]

hrmmm, that's worrying

[dankamongmen]

is _GNU_SOURCE supposed to be used with -D __MUSL__? just wondering.

[dankamongmen]

i will probably need to spin up an alpine VM to look into this. can you verify that the "missing" symbols are present in libnotcurses-core.so using objdump? i'll try to get a VM up shortly.

[wisonye]

is _GNU_SOURCE supposed to be used with -D __MUSL__? just wondering.

Oh, it doesn't matter, usually my project HAS to be compiled on MacOS/FreeBSD/AlpineLinux (sometimes another Linux distro, e.g. ArchLinux, dependons on my teammate's needs)

That __MUSL__ is a custom macro to detected whether on MUSL libc or not like this:

set MUSL (ldd /bin/ls | grep 'musl' | head -1 | cut -d ' ' -f1)

# MUSL LIBC
if test -n "$MUSL"
    # set CFLAGS "$CFLAGS -D __MUSL__ -D _GNU_SOURCE\n"
    set CFLAGS "$CFLAGS -D __MUSL__\n"
end

The linking issue still there without _GUN_SOURCE, it's NOT the reason to cause the linking error:)

[wisonye]

i will probably need to spin up an alpine VM to look into this. can you verify that the "missing" symbols are present in libnotcurses-core.so using objdump? i'll try to get a VM up shortly.

They're there except ncplane_putstr_yx

 N  wison | /home/wison   objdump -T /usr/lib/libnotcurses.so | rg notcurses
# /usr/lib/libnotcurses.so:     file format elf64-x86-64
# 0000000000000000      DF *UND*  0000000000000000  Base        notcurses_core_init
# 0000000000000000      DF *UND*  0000000000000000  Base        ncplane_notcurses
# 0000000000003740 g    DF .text  0000000000000017  Base        notcurses_init


 I  wison | /home/wison   objdump -T /usr/lib/libnotcurses-core.so | rg \
                                   -e "notcurses_core_init" \
                                   -e "notcurses_stdplane" \
                                   -e "notcurses_stop" \
                                   -e "ncplane_putstr_yx" \
                                   -e "ncplane_putegc_yx" \
                                   -e "ncpile_render" \
                                   -e "ncpile_rasterize"

# 000000000002e7a0 g    DF .text  0000000000000004 notcurses_stdplane
# 0000000000033940 g    DF .text  0000000000000093 ncplane_putegc_yx
# 00000000000350d0 g    DF .text  0000000000000e60 notcurses_core_init
# 000000000002e7b0 g    DF .text  0000000000000004 notcurses_stdplane_const
# 0000000000045c70 g    DF .text  000000000000024b ncpile_render_to_file
# 00000000000478d0 g    DF .text  0000000000000354 ncpile_rasterize
# 0000000000031320 g    DF .text  00000000000002e9 notcurses_stop
# 0000000000045ec0 g    DF .text  0000000000000464 ncpile_render
# 0000000000046330 g    DF .text  00000000000000e6 ncpile_render_to_buffer