`abort` export not provided when compiling C code that uses this symbol?

[amaanq]

This could just be totally expected and I overlooked something obvious on my end, so I apologize if so. But, I'd like to be able to export abort (or maybe exit? that also fails FYI) to be able to hot load/reload tree-sitter parser modules, sometimes these use abort/exit if a memory allocation fails, hence the usage of abort or exit. I'd appreciate any insight/alternatives! Thanks.

Version of emscripten/emsdk:
Please include the output emcc -v here

emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.53-git (ce5114b)
clang version 19.0.0git (/startdir/llvm-project febb4c42b192ed7c88c17f91cb903a59acf20baf)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /opt/emscripten-llvm/bin

Failing command line in full:
If this is compile or link-time failure please include the full failing command
along with its entire output.

#!/usr/bin/bash

set -e

emcc                                                          \
    -o stdlib.wasm                                            \
    -Os                                                       \
    -v                                                        \
    --no-entry                                                \
    -s MAIN_MODULE=2                                          \
    -s "EXPORTED_FUNCTIONS=_abort"                            \
    -s 'ALLOW_MEMORY_GROWTH'                                  \
    -s 'TOTAL_MEMORY=4MB'                                     \
    -fvisibility=hidden                                       \
    -fno-exceptions                                           \
    -xc                                                       \
    /dev/null

Full link command and output with -v appended:
Even for runtime issues it helps a lot if you can include the full link command.
Adding -v to the link command will show all of the sub-commands run which
can help us diagnose your issue.

 /opt/emscripten-llvm/bin/clang -target wasm32-unknown-emscripten -fignore-exceptions -fPIC -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=/home/amaanq/.emscripten_cache/sysroot -DEMSCRIPTEN -Werror=implicit-function-declaration -Xclang -iwithsysroot/include/fakesdl -Xc
lang -iwithsysroot/include/compat -Os -v -fvisibility=hidden -fno-exceptions -xc /dev/null -c -o /tmp/emscripten_temp_s2chziwb/null_0.o
clang version 19.0.0git (/startdir/llvm-project febb4c42b192ed7c88c17f91cb903a59acf20baf)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /opt/emscripten-llvm/bin
 (in-process)
 "/opt/emscripten-llvm/bin/clang-19" -cc1 -triple wasm32-unknown-emscripten -emit-obj -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name null -mrelocation-model pic -pic-level 2 -mframe-pointer=none -ffp-contract=on -fno-rounding-math -mconstructor-aliases -target-feature +mutabl
e-globals -target-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/home/amaanq/projects/tree-sitter -v -fcoverage-compilation-dir=/home/amaanq/projects/tree-sitter -resource-dir /opt/emscripten-llvm/lib/clang/19 -D EMSCRIPTEN -isysroot /home/amaanq/.emscripten_cache/sysroot -internal-isystem /opt/emscripten-llvm/lib/cl
ang/19/include -internal-isystem /home/amaanq/.emscripten_cache/sysroot/include/wasm32-emscripten -internal-isystem /home/amaanq/.emscripten_cache/sysroot/include -Os -Werror=implicit-function-declaration -ferror-limit 19 -fvisibility=hidden -fgnuc-version=4.2.1 -fignore-exceptions -fcolor-diagnostics -vectorize-loops -vectoriz
e-slp -iwithsysroot/include/fakesdl -iwithsysroot/include/compat -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr -o /tmp/emscripten_temp_s2chziwb/null_0.o -x c /dev/null
clang -cc1 version 19.0.0git based upon LLVM 19.0.0git default target x86_64-unknown-linux-gnu
ignoring nonexistent directory "/home/amaanq/.emscripten_cache/sysroot/include/wasm32-emscripten"
#include "..." search starts here:
#include <...> search starts here:
 /home/amaanq/.emscripten_cache/sysroot/include/fakesdl
 /home/amaanq/.emscripten_cache/sysroot/include/compat
 /opt/emscripten-llvm/lib/clang/19/include
 /home/amaanq/.emscripten_cache/sysroot/include
End of search list.
 /opt/emscripten-llvm/bin/clang --version
cache:INFO: generating system asset: symbol_lists/8def5820facfabff0785b3226fd9258b81c08609.json... (this will be cached in "/home/amaanq/.emscripten_cache/symbol_lists/8def5820facfabff0785b3226fd9258b81c08609.json" for subsequent builds)
 /usr/bin/node /usr/lib/emscripten/src/compiler.mjs /tmp/tmpy8_on035.json --symbols-only
cache:INFO:  - ok
 /opt/emscripten-llvm/bin/wasm-ld -o stdlib.wasm /tmp/emscripten_temp_s2chziwb/null_0.o -L/home/amaanq/.emscripten_cache/sysroot/lib/wasm32-emscripten/pic /home/amaanq/.emscripten_cache/sysroot/lib/wasm32-emscripten/pic/crt1_reactor.o -lGL-getprocaddr -lal -lhtml5 -lstandalonewasm-nocatch-memgrow -lstubs -lnoexit -lc -ldlmalloc
 -lcompiler_rt -lc++-noexcept -lc++abi-noexcept -lsockets -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr /tmp/tmpjuwuou71libemscripten_js_symbols.so --import-memory --strip-debug --export=stackSave --export=stackRestore --export=setThrew --export=malloc --export-if-defined=__star
t_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__start_em_lib_deps --export-if-defined=__stop_em_lib_deps --export-if-defined=__start_em_js --export-if-defined=__stop_em_js --export-if-defined=__wasm_apply_data_relocs --experimental-pic --unresolved-symbols=import-dynamic -pie --no-export-dynamic -z stack-size=6
5536 --initial-memory=4194304 --max-memory=2147483648 --entry=_initialize
 /opt/emscripten-llvm/bin/llvm-objcopy stdlib.wasm stdlib.wasm --remove-section=.debug* --remove-section=producers
 /usr/bin/wasm-emscripten-finalize --dyncalls-i64 --no-legalize-javascript-ffi --standalone-wasm stdlib.wasm -o stdlib.wasm --detect-features
emcc: error: undefined exported symbol: "_abort" [-Wundefined] [-Werror]

[sbc100]

I have a fix in #21317.

Perhaps there is a wider fix here for cases where symbols are defined both in native and JS code, but #21317 is still a good change I think.

[amaanq]

Thank you so much! I think that'll work perfectly for our use-case of using abort in standalone mode