---
name: "dmd"
section: "1"
platform: "linux"
package: "dmd"
version: "1:2.113.0-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/dmd"
---

# dmd(1)

Digital Mars D2.x Compiler

## NAME

dmd - Digital Mars D2.x Compiler

## SYNOPSIS

**dmd *files* ... \[ *-switch* ... \]**

## DESCRIPTION

**dmd** Compiles source code written in the D programming language.

## OPTIONS

- file, file.d, file.htm, file.html

  D source files to compile

- file.di

  D interface files

- file.o

  Object files to link in

- file.a

  Library files to link in

- @cmdfile

  A file to read more command-line arguments from, which may contain # single-line comments

- \-allinst

  Generate code for all template instantiations

- \-betterC

  Omit generating some runtime information and helper functions

- \-boundscheck=\[on\|safeonly\|off\]

  Bounds checks on, in @safe only, or off

- \-c

  Compile only, do not link

- \-check=\[assert\|bounds\|in\|invariant\|out\|switch\]\[=\[on\|off\]\]

  Enable or disable specific checks

- \-check=\[h\|help\|?\]

  List information on all available checks

- \-checkaction=\[D\|C\|halt\|context\]

  Behavior on assert/boundscheck/finalswitch failure

- \-checkaction=\[h\|help\|?\]

  List information on all available check actions

- \-color

  Turn colored console output on

- \-color=\[on\|off\|auto\]

  Force colored console output on or off, or only when not redirected (default)

- \-conf=*filename*

  Use config file at *filename*

- \-cov

  Perform code coverage and generate \`.lst\` file

- \-cov=ctfe

  Include code executed during CTFE in coverage report

- \-cov=*nnn*

  Require at least *nnn*% code coverage

- \-cpp=*filename*

  Use *filename* as the name of the C preprocessor to use for ImportC files

- \-D

  Generate documentation

- \-Dd*directory*

  Write documentation file to *directory*

- \-Df*filename*

  Write documentation file to *filename*

- \-d

  Silently allow deprecated features and symbols

- \-de

  Issue an error when deprecated features or symbols are used (halt compilation)

- \-dw

  Issue a message when deprecated features or symbols are used (default)

- \-debug

  Compile in debug code

- \-debug=*ident*

  Compile in debug code identified by *ident*

- \-debuglib=*libname*

  Set symbolic debug library to *libname*

- \-defaultlib=*libname*

  Set default library to *libname*

- \-deps

  Print module dependencies (imports/file/version/debug/lib)

- \-deps=*filename*

  Write module dependencies to *filename* (only imports)

- \-dllimport=\[none\|defaultLibsOnly\|externalOnly\|all\]

  Windows only: select symbols to dllimport

- \-edition\[=*NNNN*\[*filename*\]\]

  Set language edition to year *NNNN*, apply to *filename*

- \-extern-std=*standard*

  Set C++ name mangling compatibility with *standard*

- \-extern-std=\[h\|help\|?\]

  List all supported standards

- \-fIBT

  Generate Indirect Branch Tracking code

- \-fPIC

  Generate position independent code

- \-fPIE

  Generate position independent executables

- \-ftime-trace

  Turn on compile time profiler, generate JSON file with results

- \-ftime-trace-granularity=*μsecs*

  Minimum time granularity (in microseconds) traced by time profiler (default: 500)

- \-ftime-trace-file=*filename*

  Specify output file for \`-ftime-trace\`

- \-g

  Add symbolic debug info

- \-gdwarf=*version*

  Add DWARF symbolic debug info (default: 3)

- \-gf

  Emit debug info for all referenced types

- \-gs

  Always emit stack frame

- \-gx

  Add stack stomp code

- \-H

  Generate 'header' file

- \-Hd=*directory*

  Write 'header' file to *directory*

- \-Hf=*filename*

  Write 'header' file to *filename*

- \-HC=\[silent\|verbose\]

  Write C++ 'header' equivalent to stdout

- \-HC=\[?\|h\|help\]

  List available options for C++ 'header' file generation

- \-HCd=*directory*

  Write C++ 'header' file to *directory*

- \-HCf=*filename*

  Write C++ 'header' file to *filename* instead of stdout

- \--help

  Print help and exit

- \-I=*directory*

  Look for imports also in *directory*

- \-extI=*directory*

  Look for imports that are out of the currently compiling binary, used to set the module as DllImport

- \-i\[=*pattern*\]

  Include imported modules in the compilation

- \-identifiers=\[UAX31\|c99\|c11\|all\]

  Specify the non-ASCII tables for D identifiers

- \-identifiers-importc=\[UAX31\|c99\|c11\|all\]

  Specify the non-ASCII tables for ImportC identifiers

- \-ignore

  Deprecated flag, unsupported pragmas are always ignored now

- \-inline

  Do function inlining

- \-J=*directory*

  Look for string imports also in *directory*

- \-L=*linkerflag*

  Pass *linkerflag* to link

- \-lib

  Generate library rather than object files

- \-lowmem

  Enable garbage collection for the compiler

- \-m32

  Generate 32 bit code

- \-m64

  Generate 64 bit code

- \-main

  Add default main() if not present already (e.g. for unittesting)

- \-makedeps\[=*filename*\]

  Print dependencies in Makefile compatible format to *filename* or stdout.

- \-man

  Open web browser on manual page

- \-map

  Generate linker .map file

- \-mcpu=\[baseline\|avx\|native\]

  Set the target architecture for code generation

- \-mcpu=\[h\|help\|?\]

  List all architecture options

- \-mixin=*filename*

  Expand and save mixins to file specified by *filename*

- \-mv=*package.module*=*filespec*

  Use *filespec* as source file for *package.module*

- \-noboundscheck

  No array bounds checking (deprecated, use \`-boundscheck=off\`)

- \-nothrow

  Assume no Exceptions will be thrown

- \-nothrow-optimizations

  Allow skipping destructors when an Error unwinds through a nothrow function

- \-O

  Optimize

- \-o-

  Do not write object file

- \-od=*directory*

  Write object & library files to *directory*

- \-of=*filename*

  Name output file to *filename*

- \-op

  Preserve source path for output files

- \-oq

  Write object files with fully qualified file names

- \-os=*os*

  Sets target operating system to *os*

- \-P=*preprocessorflag*

  Pass *preprocessorflag* to C preprocessor

- \-preview=*name*

  Enable an upcoming language change identified by *name*

- \-preview=\[h\|help\|?\]

  List all upcoming language changes

- \-profile

  Profile runtime performance of generated code

- \-profile=gc

  Profile runtime allocations

- \-release

  Contracts and asserts are not emitted, and bounds checking is performed only in @safe functions

- \-revert=*name*

  Revert language change identified by *name*

- \-revert=\[h\|help\|?\]

  List all revertable language changes

- \-run

  Compile, link, and run the program *srcfile*

- \-shared

  Generate shared library (DLL)

- \-target=*triple*

  Use *triple* as *arch*-\[*vendor*-\]*os*\[-*cenv*\[-\<cppenv\]\]

- \-transition=*name*

  Help with language change identified by *name*

- \-transition=\[h\|help\|?\]

  List all language changes

- \-unittest

  Compile in unit tests

- \-v

  Verbose

- \-vasm

  List generated assembler for each function

- \-vcolumns

  Print character (column) numbers in diagnostics

- \-verror-style=\[digitalmars\|gnu\|sarif\]

  Set the style for file/line number annotations on compiler messages

- \-verror-supplements=*num*

  Limit the number of supplemental messages for each error (0 means unlimited)

- \-verrors=*num*

  Limit the number of error/deprecation messages (0 means unlimited)

- \-verrors=\[context\|simple\]

  Set the verbosity of error messages

- \-verrors=spec

  Show errors from speculative compiles such as \`\_\_traits(compiles, ...)\`

- \--version

  Print compiler version and exit

- \-version=*ident*

  Compile in version code identified by *ident*

- \-vgc

  List all GC allocations including hidden ones

- \-visibility=\[default\|hidden\|public\]

  Default visibility of symbols

- \-vtls

  List all variables going into thread local storage

- \-vtemplates\[=list-instances\]

  List statistics on template instantiations

- \-w

  Warnings as errors (compilation will halt)

- \-wi

  Warnings as messages (compilation will continue)

- \-wo

  Warnings about use of obsolete features (compilation will continue)

- \-X

  Generate JSON file

- \-Xf=*filename*

  Write JSON file to *filename*

- \-Xcc=*driverflag*

  Pass *driverflag* to linker driver (cc)

## TRANSITIONS

Language changes listed by **-transition=id**:

- *field*

  List all non-mutable fields which occupy an object instance

- *complex*

  Give deprecation messages about all usages of complex or imaginary types

- *tls*

  List all variables going into thread local storage

- *in*

  List all usages of 'in' on parameter

## LINKING

Linking is done directly by the **dmd** compiler after a successful compile. To prevent **dmd** from running the linker, use the **-c** switch.

The actual linking is done by running **gcc**. This ensures compatibility with modules compiled with **gcc**.

## FILES

- */etc/dmd.conf*

  System wide **dmd** config file. See **[dmd.conf(5)](/dmd.conf/5.md)** for details.

## ENVIRONMENT

The D compiler dmd uses the following environment variables:

- DFLAGS

  The value of **DFLAGS** is treated as if it were appended on the command line to **dmd**.

## AUTHOR

Copyright (c) 1999-2026 by The D Language Foundation written by Walter Bright

## ONLINE DOCUMENTATION

https://dlang.org/dmd.html ⟨https://dlang.org/dmd.html⟩

## SEE ALSO

[**dmd.conf**(5)](/dmd.conf/5.md) **rdmd**(1) **dumpobj**(1) **obj2asm**(1) [**gcc**(1)](/gcc/1.md)