CRYSTAL-BUILD(1) Crystal Compiler Command Line Reference Guide (NAME) crystal-build - Crystal (SYNOPSIS) crystal build [options] [programfile] [--] [arguments] (OPTIONS) --cross-compile (object file) (cross compilation) . . . -d, --debug (debug symbols). lldb gdb valgrind . --no-debug . -D FLAG, --define FLAG . . (target triple) --target-triple . --emit [asm|llvm-bc|llvm-ir|obj] . LLVM IR LLVM (object) . --x86-asm-syntax [att|intel] --emit=asm. att AT&T GNU Assembler . intel Intel Windows . --frame-pointers [auto|always|non-leaf] (frame pointers). --frame-pointers=auto debug release ( ). --frame-pointers=always non-leaf (non-leaf) . -f text|json, --format text|json . text . json (parse) . --error-trace (error trace). . --ll LLVM . --link-flags FLAGS (linker). . <> . --mcpu CPU (CPU) . -mcpu LLVM . CPU Crystal --mcpu help . --mcpu native CPU . --mattr CPU SIMD. CPU . -mattr LLVM . llvm-as < /dev/null | llc -march=xyz -mattr=help . --mcmodel default|kernel|tiny|small|medium|large (code model) . --code-model LLVM . --no-color . --no-codegen (parse) . -o FILE, --output FILE . (: ). --prelude (prelude) . (garbage collector) . --prelude=empty . . -O LEVEL : 0 () 1 2 3. OPTIMIZATIONS . --release (release). -O3 --single-module -s, --stats . . -p, --progress . -t, --time . --single-module LLVM . (type) LLVM . --release . --threads NUM (threads) . . --target TRIPLE (target triple) . llvm . --verbose . --static (statically linked). --stdin-filename FILENAME STDIN. crystal 1.21.0 2026-07-23 CRYSTAL-BUILD(1)