Dart -ing: Dart VMのコマンドオプション

dartコマンドで起動するDart VMには、Dart VMに渡すフラグを指定することができます。dartコマンドの実行時に --print_flags オプションを指定すると、フラグの一覧と、そのフラグの現在の状態を表示することができます。

フラグに値を指定するには、= に続けて値を指定します。例えば --code_heap_size=8 のようになります。真偽値（有効無効）で指定するものについては、true または false を指定します。例えば --enable_type_checks=true のようになります。

真偽値を指定するフラグには、フラグ名の先頭に no_ を付けることで、そのフラグを無効化することもできます。例えば、enable_type_checks フラグを無効化するには、コマンドラインで --no_enable_type_checks と指定します。

おそらくバージョンによって使えるオプションは変わりますが、現時点での最新版（リビジョン4577）のDart VMには次のフラグが用意されています。リストにある値は、オプションを指定しなかった場合のデフォルト値です。

verify_implements: false (Verify that all classes implement their interface.)
trace_type_finalization: false (Trace type finalization.)
trace_class_finalization: false (Trace class finalization.)
print_classes: false (Prints details about loaded classes.)
trace_bailout: false (Print bailout from new compiler.)
use_new_compiler: false (Try to use the new compiler backend.)
deoptimization_counter_threshold: 5 (How many times we allow deoptimization before we disallow certain optimizations)
trace_compiler: false (Trace compiler operations.)
disassemble: false (Disassemble dart code.)
print_stack_trace_at_throw: false (Prints a stack trace everytime a throw occurs.)
ignore_unrecognized_flags: false (Ignore unrecognized flags.)
print_flags: false (Print flags as they are being parsed.)
print_flow_graph: false (Print the IR flow graph.)
code_heap_size: 8 (code heap size in MB,e.g: --code_heap_size=8 allocates a 8MB old gen heap)
old_gen_heap_size: 512 (old gen heap size in MB,e.g: --old_gen_heap_size=1024 allocates a 1024MB old gen heap)
new_gen_heap_size: 32 (new gen heap size in MB,e.g: --new_gen_heap_size=64 allocates a 64MB new gen heap)
gc_at_alloc: false (GC at every allocation.)
verify_after_gc: false (Enables heap verification after GC.)
verify_before_gc: false (Enables heap verification before GC.)
verbose_gc: false (Enables verbose GC.)
trace_isolates: false (Trace isolate creation and shut down.)
report_invocation_count: false (Count function invocations and report.)
generate_gdb_symbols: false (Generate symbols of generated dart functions for debugging with GDB)
trace_optimization: false (Trace optimizations.)
silent_warnings: false (Silence warnings.)
warning_as_error: false (Treat warnings as errors.)
trace_parser: false (Trace parser operations.)
enable_type_checks: false (Enable type checks.)
enable_asserts: false (Enable assert statements.)
trace_resolving: false (Trace resolving.)
print_tokens: false (Print scanned tokens.)
disassemble_stubs: false (Disassemble generated stubs.)
use_slow_path: false (Set to true for debugging & verifying the slow paths.)
inline_alloc: true (Inline allocation of objects.)
time_all: false (Time all functionality)
time_total_runtime: false (time_total_runtime)
time_bootstrap: false (time_bootstrap)
time_compilation: false (time_compilation)
time_isolate_initialization: false (time_isolate_initialization)
time_creating_snapshot: false (time_creating_snapshot)
time_script_loading: false (time_script_loading)
verify_on_transition: false (Verify on dart <==> VM.)
print_stop_message: true (Print stop message.)
trace_runtime_calls: false (Trace runtime calls.)
trace_patching: false (Trace patching of code.)
trace_ic: false (trace IC handling)
trace_deopt: false (Trace deoptimization)
inline_cache: true (enable inline caches)
optimization_invocation_threshold: 1000 (Number of invocations before a function is optimized, -1 means never.)
print_ic_in_optimized: false (Debugging helper to identify potential performance pitfalls.)
trace_functions: false (Trace entry of each function.)
print_scopes: false (Print scopes of local variables.)
print_ast: false (Print abstract syntax tree.)
compiler_stats: false (Compiler stat counters.)
intrinsify: true (Instrinsify when possible)
trace_natives: false (Trace invocation of natives)
print_bootstrap: false (Print the bootstrap source.)
trace_type_checks: false (Trace runtime type checks.)
trace_intrinsified_natives: false (Report if any of the intrinsified natives are called)