src/tools/findcc.sh


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#!/bin/sh
# prints the first c compiler that accepts c23 #embed, which every core needs to
# take in its genome (src/core/genome.h). clang 19 and gcc 15 are the first
# releases with it, and both find #embed files through --embed-dir. a CC
# already in the environment is tried first.
#   src/tools/findcc.sh           a native compiler
#   src/tools/findcc.sh --wasm    a clang that also targets wasm32
# exits 1, naming what was tried, when nothing fits.
case "${1:-}" in
    --help|-h) printf '%s\n' 'usage: src/tools/findcc.sh [--wasm]' 'prints a c compiler that supports #embed; --wasm also requires the wasm32 target.' 'environment: CC is tried first.'; exit 0 ;;
    --wasm|'') ;;
    *) echo "findcc: unknown option $1; use --help for usage" >&2; exit 2 ;;
esac
wasm=${1:-}
dir=$(mktemp -d "${TMPDIR:-/tmp}/findcc.XXXXXX") || exit 1
trap 'rm -rf "$dir"' EXIT
mkdir "$dir/data"
printf 'ab' > "$dir/data/probe.bin"
printf 'static const unsigned char probe[] = {\n#embed "probe.bin"\n};\nint main(void) { return sizeof probe == 2 ? 0 : 1; }\n' > "$dir/probe.c"
tried=""
for cc in ${CC:-} cc clang gcc clang-22 clang-21 clang-20 clang-19 gcc-16 gcc-15 /opt/homebrew/opt/llvm/bin/clang /usr/local/opt/llvm/bin/clang; do
    command -v "$cc" >/dev/null 2>&1 || continue
    tried="$tried $cc"
    if [ -n "$wasm" ]; then
        "$cc" --target=wasm32 -nostdlib -w --embed-dir="$dir/data" -c "$dir/probe.c" -o "$dir/probe.o" >/dev/null 2>&1 || continue
    else
        "$cc" -w --embed-dir="$dir/data" "$dir/probe.c" -o "$dir/probe" >/dev/null 2>&1 || continue
    fi
    echo "$cc"
    exit 0
done
echo "findcc: no c compiler with #embed${wasm:+ and wasm32} (tried:${tried:- nothing}); install clang 19 or gcc 15, or set CC" >&2
exit 1