-% NITG(1)
-
# NAME
nitc - compiles Nit programs.
Internally, nitc rely on the presence of a C compiler. Usually gcc (but nitc was successfully tested with clang).
A compilation directory is therefore created and (re-)used.
-By default, the compilation directory is named `.nit_compile`.
+By default, the compilation directory is named `nit_compile` and is removed after the compilation.
(see `--compile-dir` for details.)
Currently, because Nit is still in heavy development, the compilation directory is not cleaned after the compilation.
## MESSAGES
-`-W`, `--warn`
-: Show additional warnings (advices).
+### `-W`, `--warn`
+Show additional warnings (advices).
+
+By default, only important warnings are displayed.
+May be overridden by `-w`.
+
+Important warnings are displayed by default. A warning is considered important when:
- By default, only important warnings are displayed.
- May be overridden by `-w`.
+* There is a simple correction.
+* There is no reason to let the code this way.
+* There is always a real issue (no false positive).
- Important warnings are displayed by default. A warning is considered important when:
+Other warnings, called advices, are not displayed by default to avoid filling the terminal with
+unwanted information.
+A warning is considered an advice when:
- * There is a simple correction.
- * There is no reason to let the code this way.
- * There is always a real issue (no false positive).
+* The correction could be complex. e.g. require a refactorisation or an API change.
+* The correction cannot be done. e.g. Code that use a deprecated API for some compatibility reason.
+* There is not a real issue (false positive). Note that this should be unlikely.
+* Transitional: While a real important warning, it fires a lot in current code, so a transition is needed
+in order to let people fix them before promoting the advice to an important warning.
- Other warnings, called advices, are not displayed by default to avoid filling the terminal with
- unwanted information.
- A warning is considered an advice when:
+### `-w`, `--warning`
+Show/hide a specific warning.
- * The correction could be complex. e.g. require a refactorisation or an API change.
- * The correction cannot be done. e.g. Code that use a deprecated API for some compatibility reason.
- * There is not a real issue (false positive). Note that this should be unlikely.
- * Transitional: While a real important warning, it fires a lot in current code, so a transition is needed
- in order to let people fix them before promoting the advice to an important warning.
+Each type of warning can be individually displayed or hidden.
+The `-w` option takes the name of a warning (displayed at the end of the warning message, between parentheses) to activate it;
+and "no-{name}" to disable it.
+It has precedence over -q and -W.
+Multiple `-w` can be given.
-`-w`, `--warning`
-: Show/hide a specific warning.
+To show only `missing-doc` warnings in standard"
- Each type of warning can be individually displayed or hidden.
- The `-w` option takes the name of a warning (displayed at the end of the warning message, between parentheses) to activate it;
- and "no-{name}" to disable it.
- It has precedence over -q and -W.
- Multiple `-w` can be given.
+ $ nitc -q -w missing-doc standard
- To show only `missing-doc` warnings in standard"
+To show all warnings and advices, except `missing-doc`:
- $ nitc -q -w missing-doc standard
+ $ nitc -W -w no-missing-doc standard
- To show all warnings and advices, except `missing-doc`:
+To show important warnings except `useless-type-test`, but not advice except `missing-doc`:
- $ nitc -W -w no-missing-doc standard
+ $ nitc -w missing-doc -w no-useless-type-test standard
- To show important warnings except `useless-type-test`, but not advice except `missing-doc`:
+### `-q`, `--quiet`
+Do not show warnings.
+May be overridden by `-w`
- $ nitc -w missing-doc -w no-useless-type-test standard
+### `--stop-on-first-error`
+Just display the first encountered error then stop.
-`-q`, `--quiet`
-: Do not show warnings.
- May be overridden by `-w`
+By default, nitc tries to detect and display more than one error before aborting the compilation.
-`--stop-on-first-error`
-: Just display the first encountered error then stop.
+### `--no-color`
+Do not use color to display errors and warnings.
- By default, nitc tries to detect and display more than one error before aborting the compilation.
+Also, do not echo the line.
+This options is mainly used by scripts and tools that need parsable error messages.
-`--no-color`
-: Do not use color to display errors and warnings.
+### `-v`, `--verbose`
+Additional messages from the tool.
+Multiple `-v` can be given to improve the verbosity.
- Also, do not echo the line.
- This options is mainly used by scripts and tools that need parsable error messages.
+With one `-v`, there is constant number of lines.
+With two `-v`, the number of lines is proportional to the number of modules.
+With three `-v`, the number of lines is proportional to the number of definition of classes.
+With four `-v`, the number of lines is proportional to the number of definition of properties.
-`-v`, `--verbose`
-: Additional messages from the tool.
- Multiple `-v` can be given to improve the verbosity.
+### `--log`
+Generate various log files.
- With one `-v`, there is constant number of lines.
- With two `-v`, the number of lines is proportional to the number of modules.
- With three `-v`, the number of lines is proportional to the number of definition of classes.
- With four `-v`, the number of lines is proportional to the number of definition of properties.
+The tool will generate some files in the logging directory (see `--log-dir`).
+These files are intended to the advanced user and the developers of the tools.
-`--log`
-: Generate various log files.
- Currently unused.
+### `--log-dir`
+Directory where to generate log files.
-`--log-dir`
-: Directory where to generate log files.
- Currently unused.
+By default the directory is called `logs` in the working directory.
-`-h`, `-?`, `--help`
-: Show Help (the list of options).
+### `-h`, `-?`, `--help`
+Show Help (the list of options).
-`--version`
-: Show version and exit.
+### `--version`
+Show version and exit.
## PATHS
-`-I`, `--path`
-: Add an additional include path.
+### `-I`, `--path`
+Add an additional include path.
- This option is used to indicate an additional path of a directory containing Nit libraries.
+This option is used to indicate an additional path of a directory containing Nit libraries.
- The path added with `-I` are searched before those added by the environment variable `NIT_PATH`.
+The path added with `-I` are searched before those added by the environment variable `NIT_PATH`.
- May be used more than once.
+May be used more than once.
-`-o`, `--output`
-: Output executable name.
+### `-o`, `--output`
+Filename of the generated executable.
- Indicates the path and name of the produced executable.
+Indicates the path and name of the produced executable.
- Note: it is better to use `--dir` if only the directory is important.
- This way, the platform extension will be correctly set.
+Note: it is better to use `--dir` if only the directory is important.
+This way, the platform extension will be correctly set.
- `-o` is not usable if multiple programs are compiled at once.
+`-o` is not usable if multiple programs are compiled at once.
-`--dir`
-: Output directory.
+### `--dir`
+Output directory.
- Produce the executables in the given directory instead of the current directory.
+Produce the executables in the given directory instead of the current directory.
-`--nit-dir`
-: Base directory of the Nit installation.
+### `--nit-dir`
+Base directory of the Nit installation.
- Has precedence over the environment variable `NIT_DIR`.
+Has precedence over the environment variable `NIT_DIR`.
## COMPILATION
-`--compile-dir`
-: Directory used to generate temporary files.
+### `--compile-dir`
+Directory used to generate temporary files.
+
+By default, it is named `nit_compile` and created in the current directory and destroyed after the compilation.
+
+If the option `--compile_dir` or `--no-cc` is used, then the directory is not destroyed and let as is.
+
+### `--no-cc`
+Do not invoke the C compiler.
- By default, it is named `.nit_compile`.
+Files in the compilation directory are generated but the C compiler is not invoked.
-`--no-cc`
-: Do not invoke the C compiler.
+This option is mainly used to produce C files distributable then compilable on system that do not have a Nit compiler (e.g. embedded system).
+In this case, it is suggested to also use the options `--dir`, `--compile-dir` and `--semi-global`.
- Files in the compilation directory are generated but the C compiler is not invoked.
+ $ nitc examples/hello_world.nit --no-cc --dir hello --compile-dir hello --semi-global
- This option is mainly used to produce C files distributable then compilable on system that do not have a Nit compiler (e.g. embedded system).
- In this case, it is suggested to also use the options `--dir`, `--compile-dir` and `--semi-global`.
+Will produce a `hello` directory that contains the required C files to finish the compilation.
+Only the C files required for the program are generated.
+The final binary will be generated in the same directory.
- $ nitc examples/hello_world.nit --no-cc --dir hello --compile-dir hello --semi-global
+Note that, to be useful, the compilation directory is not destroyed when `--no-cc` is used.
- Will produce a `hello` directory that contains the required C files to finish the compilation.
- Only the C files required for the program are generated.
- The final binary will be generated in the same directory.
+### `-m`, `--mixin`
+Additional module to mix-in.
-`-m`
-: Additional module to mix-in.
+Additional modules are imported and refine the main module of the program.
+This has basically the same effect than implementing a specific module that imports the main module of the program then each one of the mix-in modules.
+May be used more than once.
- Additional modules are imported and refine the main module of the program.
- This has basically the same effect than implementing a specific module that imports the main module of the program then each one of the mix-in modules.
- May be used more than once.
+This is option is used to weave additional behaviors to existing programs.
+Modules designated to bring features to programs by refining basic or specialized services, without any intervention of the main program, are good candidates to be used with the `-m` option.
+E.g. `hash_debug`.
- This is option is used to weave additional behaviors to existing programs.
- Modules designated to bring features to programs by refining basic or specialized services, without any intervention of the main program, are good candidates to be used with the `-m` option.
- E.g. `hash_debug`.
+An other usage of the `-m` option is to compile program to a specific platform. E.g. `emscripten` or `android`.
- An other usage of the `-m` option is to compile program to a specific platform. E.g. `emscripten` or `android`.
+A last usage is to develop programs as product lines with a main basic module (vanilla) and specific distinct features as flavor modules, then to combine them at compile-time.
- A last usage is to develop programs as product lines with a main basic module (vanilla) and specific distinct features as flavor modules, then to combine them at compile-time.
+ $ nitc prog_vanilla.nit -m feature_chocolate.nit -m feature_cherry.nit
- $ nitc prog_vanilla.nit -m feature_chocolate.nit -m feature_cherry.nit
+### `-D`, `--define`
+Define a specific property.
-`-D`, `--define`
-: Define a specific property.
+The `-D` option allows to refine a top-level method at compile-time.
+This has basically the same effect than implementing a specific module that imports the main module of the program and refines the designated methods.
- The `-D` option allows to refine a top-level method at compile-time.
- This has basically the same effect than implementing a specific module that imports the main module of the program and refines the designated methods.
+The designated method must be top-level function with no parameters that returns a Bool, an Int or a String.
- The designated method must be top-level function with no parameters that returns a Bool, an Int or a String.
+The argument of the `-D` option is "{name}={value}".
+For Bool, the argument can also be just "{name}", in this case, the value is considered to be `true`.
- The argument of the `-D` option is "{name}={value}".
- For Bool, the argument can also be just "{name}", in this case, the value is considered to be `true`.
+ $ nitc foo.nit -D prefix=/opt/foo -D port=8080 -D with_ssl
- $ nitc foo.nit -D prefix=/opt/foo -D port=8080 -D with_ssl
+### `--release`
+Compile in release mode and finalize application.
-`--release`
-: Compile in release mode and finalize application.
+Currently, this only affect the android platform.
- Currently, this only affect the android platform.
+### `-g`, `--debug`
+Compile in debug mode.
+
+Currently removes gcc optimizations.
+Also preserves the source-files directory for C-debuggers.
+
+For more debugging-related options, see also `--hardening` and `NIT_GC_OPTION`
## COMPILATION MODES
-`nitc` includes distinct compilation modes.
+### `nitc` includes distinct compilation modes.
-`--separate`
-: Use separate compilation (default mode).
+### `--separate`
+Use separate compilation (default mode).
- In separate compilation, modules are compiled independently of their programs.
- This makes the recompilation of programs faster since only the modified files need to be recompiled.
+In separate compilation, modules are compiled independently of their programs.
+This makes the recompilation of programs faster since only the modified files need to be recompiled.
-`--global`
-: Use global compilation.
+### `--global`
+Use global compilation.
- The produced executables may become huge and the compilation time is prohibitive.
- But sometime, they are faster.
+The produced executables may become huge and the compilation time is prohibitive.
+But sometime, they are faster.
- In practice, `--semi-global` produces nearly as fast but smaller executables.
+In practice, `--semi-global` produces nearly as fast but smaller executables.
-`--erasure`
-: Erase generic types.
+### `--erasure`
+Erase generic types.
- Like `--separate` but use an erasure dynamic typing policy for generics and virtual types.
- Usually you do not need this, even if you understand the previous sentence.
+Like `--separate` but use an erasure dynamic typing policy for generics and virtual types.
+Usually you do not need this, even if you understand the previous sentence.
## SEMI-GLOBAL OPTIMIZATIONS
Therefore, with these options, the produced executables may be faster and smaller but the recompilation time
will increase.
-`--semi-global`
-: Enable all semi-global optimizations.
+### `--semi-global`
+Enable all semi-global optimizations.
+
+### `--rta`
+Activate RTA (Rapid Type Analysis).
+
+This option only make sense in `--erasure` to enable some semi-global optimizations.
+
+RTA is implicitly enabled in `--separate` and `--global`.
+
+### `--inline-coloring-numbers`
+Inline colors and ids (semi-global).
+
+### `--inline-some-methods`
+Allow the separate compiler to inline some methods (semi-global).
+Need `--rta`.
+
+### `--direct-call-monomorph`
+Allow the separate compiler to direct call monomorphic sites (semi-global).
+Need `--rta`.
+
+### `--direct-call-monomorph0`
+Allow the separate compiler to direct call monomorphic sites (semi-global).
+Need `--rta`.
+
+The difference with the non-zero option is internal:
+with this option, the monomorphism is looked-at on the mmethod level and not at the callsite level.
+
+### `--skip-dead-methods`
+Do not compile dead methods (semi-global).
+Need `--rta`.
+
+## LINK-BOOST OPTIMIZATIONS
+
+In `--separate` and in `--erasure` modes, some optimization can be gained by hijacking the linker process.
+
+Warning: these optimisations are not portable since they use extra features of the GNU linker `ld`.
+However, there is very few reasons to not use them if GNU `ld` is available.
+
+### `--link-boost`
+Enable all link-boost optimizations.
-`--rta`
-: Activate RTA (Rapid Type Analysis).
+### `--colors-are-symbols`
+Store colors as symbols instead of static data.
- This option only make sense in `--erasure` to enable some semi-global optimizations.
+By default, the various identifiers used to implement OO-mechanisms are stored as genuine constant static variables.
- RTA is implicitly enabled in `--separate` and `--global`.
+This option uses linker symbols to encode these identifiers.
+This makes the compiled program faster since less indirections are required to get the values.
+It also produces executables that are a little bit smaller since static memory does not have to store the colors.
-`--inline-coloring-numbers`
-: Inline colors and ids (semi-global).
+### `--substitute-monomorph`
+Replace monomorphic trampolines with direct calls.
-`--inline-some-methods`
-: Allow the separate compiler to inline some methods (semi-global).
- Need `--rta`.
+Late-binding is implemented with *trampolines*, that are small functions that just select and jump the to right implementations.
+If, at link-time, is it known that the target will always by the same implementation then all calls to the trampoline are replaced by
+direct calls to this single implementation.
-`--direct-call-monomorph`
-: Allow the separate compiler to direct call monomorphic sites (semi-global).
- Need `--rta`.
+Note that using trampolines as indirection slows down the executable.
+However, it is expected that the gain of monomorphic direct-calls overcompensates the additional indirections in polymorphic trampoline-calls.
-`--skip-dead-methods`
-: Do not compile dead methods (semi-global).
- Need `--rta`.
+Note: automatically enable option `--trampoline-call`.
+
+## POTENTIAL OPTIMIZATIONS
+
+These optimisation are not enabled by default as they are counter-effective in most cases.
+
+### `--guard-call`
+Guard VFT calls with a direct call.
+
+### `--type-poset`
+Build a poset of types to create more condensed tables.
+
+The drawback is that more time and memory are used by the compilation process.
## DANGEROUS OPTIMIZATIONS
In fact, these options are mainly used to bench the compilation results.
-`--no-check-all`
-: Disable all tests (dangerous).
+### `--no-check-all`
+Disable all tests (dangerous).
-`--no-check-covariance`
-: Disable type tests of covariant parameters (dangerous).
+### `--no-check-covariance`
+Disable type tests of covariant parameters (dangerous).
-`--no-check-attr-isset`
-: Disable isset tests before each attribute access (dangerous).
+### `--no-check-attr-isset`
+Disable isset tests before each attribute access (dangerous).
-`--no-check-assert`
-: Disable the evaluation of explicit `assert` and `as` (dangerous).
+### `--no-check-assert`
+Disable the evaluation of explicit `assert` and `as` (dangerous).
-`--no-check-autocast`
-: Disable implicit casts on unsafe expression usage (dangerous).
+### `--no-check-autocast`
+Disable implicit casts on unsafe expression usage (dangerous).
-`--no-check-null`
-: Disable tests of null receiver (dangerous).
+### `--no-check-null`
+Disable tests of null receiver (dangerous).
-`--no-check-erasure-cast`
-: Disable implicit casts on unsafe return with erasure-typing policy (dangerous).
+### `--no-check-erasure-cast`
+Disable implicit casts on unsafe return with erasure-typing policy (dangerous).
## UNOPTIMIZATIONS
These options are used to debug or to bench the compilation results.
Usually you do not need them since they make the generated code slower.
-`--hardening`
-: Generate contracts in the C code against bugs in the compiler.
+### `--hardening`
+Generate contracts in the C code against bugs in the compiler.
+
+### `--no-shortcut-range`
+Always instantiate a range and its iterator on 'for' loops.
-`--no-shortcut-range`
-: Always instantiate a range and its iterator on 'for' loops.
+### `--no-union-attribute`
+Put primitive attributes in a box instead of an union.
-`--no-union-attribute`
-: Put primitive attributes in a box instead of an union.
+### `--no-shortcut-equal`
+Always call == in a polymorphic way.
-`--no-shortcut-equal`
-: Always call == in a polymorphic way.
+### `--no-tag-primitives`
+Use only boxes for primitive types.
-`--no-inline-intern`
-: Do not inline call to intern methods.
+The separate compiler uses tagged values to encode common primitive types like Int, Bool and Char.
+This option disables tags and forces such primitive values to be boxed.
+The drawback is that each boxing costs a memory allocation thus increases the amount of work for the garbage collector.
-`--colo-dead-methods`
-: Force colorization of dead methods.
+However, in some cases, it is possible that this option improves performance since the absence of tags simplify the implementation
+of OO mechanisms like method calls or equality tests.
-`--no-gcc-directive`
-: Disable advanced gcc directives for optimization.
+### `--no-inline-intern`
+Do not inline call to intern methods.
+### `--colo-dead-methods`
+Force colorization of dead methods.
+
+### `--no-gcc-directive`
+Disable advanced gcc directives for optimization.
+
+### `--trampoline-call`
+Use an indirection when calling.
+
+Just add the trampolines of `--substitute-monomorph` without doing any additionnal optimizations.
## INTERNAL OPTIONS
These options can be used to control the fine behavior of the tool.
They are useless for a normal user.
-`--disable-phase`
-: Disable a specific phase; use `list` to get the list.
+### `--disable-phase`
+Disable a specific phase; use `list` to get the list.
+
+### `--only-parse`
+Only proceed to parse files.
+
+### `--only-metamodel`
+Stop after meta-model processing.
-`--only-parse`
-: Only proceed to parse files.
+### `--ignore-visibility`
+Do not check, and produce errors, on visibility issues.
-`--only-metamodel`
-: Stop after meta-model processing.
+### `--no-main`
+Do not generate main entry point.
-`--ignore-visibility`
-: Do not check, and produce errors, on visibility issues.
+### `--no-stacktrace`
+Disable the generation of stack traces.
-`--no-main`
-: Do not generate main entry point.
+With this option, the compiled program will not display stack traces on runtime errors.
-`--stacktrace`
-: Control the generation of stack traces.
+Because stack traces rely on libunwind, this option might be useful in order to generate more portable binaries
+since libunwind might be non available on the runtime system (or available with an ABI incompatible version).
-`--max-c-lines`
-: Maximum number of lines in generated C files. Use 0 for unlimited.
+The generated C is API-portable and can be reused, distributed and compiled on any supported system.
+If the option `--no-stacktrace` is not used but the development files of the library `libunwind` are not available, then a warning will be displayed
+and stack trace will be disabled.
-`--group-c-files`
-: Group all generated code in the same series of files.
+Note that the `--no-stacktrace` option (or this absence) can be toggled manually in the generated Makefile (search `NO_STACKTRACE` in the Makefile).
+Moreover, the environment variable `NIT_NO_STACK` (see bellow) can also be used at runtime to disable stack traces.
-`--make-flags`
-: Additional options to the `make` command.
+### `--max-c-lines`
+Maximum number of lines in generated C files. Use 0 for unlimited.
- $ nitc foo.nit --make-flags 'CC=clang' --make-flags 'CFLAGS="-O0 -g"'
+### `--group-c-files`
+Group all generated code in the same series of files.
-`--typing-test-metrics`
-: Enable static and dynamic count of all type tests.
+### `--make-flags`
+Additional options to the `make` command.
-`--invocation-metrics`
-: Enable static and dynamic count of all method invocations.
+ $ nitc foo.nit --make-flags 'CC=clang' --make-flags 'CFLAGS="-O0 -g"'
-`--isset-checks-metrics`
-: Enable static and dynamic count of isset checks before attributes access.
+### `--typing-test-metrics`
+Enable static and dynamic count of all type tests.
-`--tables-metrics`
-: Enable static size measuring of tables used for vft, typing and resolution.
+### `--invocation-metrics`
+Enable static and dynamic count of all method invocations.
-`--set-dummy-tool`
-: Set toolname and version to DUMMY. Useful for testing.
+### `--isset-checks-metrics`
+Enable static and dynamic count of isset checks before attributes access.
-`--bash-completion`
-: Generate bash_completion file for this program.
+### `--tables-metrics`
+Enable static size measuring of tables used for vft, typing and resolution.
-`--stub-man`
-: Generate a stub manpage in pandoc markdown format.
+### `--set-dummy-tool`
+Set toolname and version to DUMMY. Useful for testing.
+### `--bash-completion`
+Generate bash_completion file for this program.
+
+### `--stub-man`
+Generate a stub manpage in pandoc markdown format.
+
+### `--keep-going`
+Continue after errors, whatever the consequences.
+
+The tool does not stop after some errors but continue until it produces incorrect result, crashes, erases the hard drive, or just continue forever in an infinite loop.
+This option is used to test the robustness of the tools by allowing phases to progress on incorrect data.
+
+### `--sloppy`
+Force lazy semantic analysis of the source-code.
+
+Analysis of methods is thus done only when required.
+This option breaks the behavior of most of the tools since errors in methods are undetected until the method is required in some processing.
# ENVIRONMENT VARIABLES
-`NIT_DIR`
-: Base directory of the Nit installation.
+### `NIT_DIR`
+Base directory of the Nit installation.
+
+When the `NIT_DIR` environment variable is set then it specifies the path of the Nit install directory.
+
+This directory is used to locate binaries, shared files and the common libraries.
+
+When unset, the directory is guessed according to some heuristic.
+
+The `--nit-dir` option also set the base directory of the Nit installation but has precedence.
+
+### `NIT_PATH`
+Additional include paths.
- When the `NIT_DIR` environment variable is set then it specifies the path of the Nit install directory.
+The `NIT_PATH` environment variable contains paths of directories containing Nit libraries.
+Each path is separated with a column (`:`).
- This directory is used to locate binaries, shared files and the common libraries.
+The `-I` option also add additional paths.
- When unset, the directory is guessed according to some heuristic.
+### `NIT_GC_OPTION`
+Runtime control of the garbage collector.
- The `--nit-dir` option also set the base directory of the Nit installation but has precedence.
+The behavior of the GC of the executables produced by nitc can be tuned with this environment variable.
-`NIT_PATH`
-: Additional include paths.
+The environment variable is used when programs are executed, not when they are compiled.
+Thus, you do not need to recompile programs in order to tweak their GC options.
- The `NIT_PATH` environment variable contains paths of directories containing Nit libraries.
- Each path is separated with a column (`:`).
+Available values are:
- The `-I` option also add additional paths.
+* boehm: use the Boehm-Demers-Weiser's conservative garbage collector (default).
+* malloc: disable the GC and just use `malloc` without doing any `free`.
+* large: disable the GC and just allocate a large memory area to use for all instantiation.
+* help: show the list of available options.
-`NIT_GC_OPTION`
-: Runtime control of the garbage collector.
+### `NIT_NO_STACK`
+Runtime control of stack traces.
- The behavior of the GC of the executables produced by nitc can be tuned with this environment variable.
+By default, stack traces are printed when a runtime errors occurs during the execution of a compiled program.
+When setting this environment variable to a non empty value, such stack traces are disabled.
- The environment variable is used when programs are executed, not when they are compiled.
- Thus, you do not need to recompile programs in order to tweak their GC options.
+The environment variable is used when programs are executed, not when they are compiled.
+Thus, you do not need to recompile programs in order to disable generated stack traces.
- Available values are:
+Note that stack traces require that, during the compilation, development files of the library `libunwind` are available.
+If they are not available, then programs are compiled without any stack trace support.
- * boehm: use the Boehm-Demers-Weiser's conservative garbage collector (default).
- * malloc: disable the GC and just use `malloc` without doing any `free`.
- * large: disable the GC and just allocate a large memory area to use for all instantiation.
- * help: show the list of available options.
+To completely disable stack traces, see the option `--no-stacktrace`.
# SEE ALSO
nitlanguage / nit.git / blobdiff