Build System

Compiler Backends

DCR supports 4 compilation backends. Selection is automatic based on file extension.

Backend	Files	When used
unix_cc	.c, .cpp, .cxx, .cc, .S	gcc/clang on Linux/macOS/BSD
msvc	.c, .cpp, .cxx, .cc	Windows (cl, clang-cl)
gas	.s	ARM/ARM64 assembler (no preprocessor)
nasm	.asm	x86/x86_64 assembler

Unix CC

• Compiler resolved via resolve_compiler(): DCR_COMPILER > DCR_CC > [toolchain] > build.compiler > PATH
• Supports .d files for header dependency tracking
• Flags: -std=, -MMD -MF, -c -o, -I, -L, -l

MSVC

• Supports cl.exe and clang-cl.exe
• Flags: /std:, /Fo:, /Fe:, /I, /link

GAS / NASM

• GAS: -I, -c -o, --defsym
• NASM: -I, -o, -D, -f (format: win64/elf64/macho64/macho32/elf32)

Incremental Builds

Three levels of incrementality:

1. mtime — if output is newer than all inputs, skip
2. .d files — header change tracking (including transitive)
3. SHA256 fingerprint — recompile if compiler flags changed (stored in .dcr_fingerprint)

Parallel Compilation

• thread::scope for thread pool
• Atomic task queue (AtomicU64)
• Mutex on stdout (OUTPUT_MUTEX)
• Thread count = available_parallelism()

Build Kinds

Kind	Type	Path (Linux example)
bin	Executable	target/<triple>/<profile>/<name> (.exe on Windows)
staticlib	Static library	target/<triple>/<profile>/lib<name>.a (.lib)
sharedlib	Dynamic library	target/<triple>/<profile>/lib<name>.so (.dll/.dylib)
efi	UEFI application	target/<triple>/<profile>/<name>.efi
elf	ELF without stdlib	target/<triple>/<profile>/<name>
none	Compile only, no link	—
custom	Full filename+extension control	target/<triple>/<profile>/<filename>.<extension>

Build Steps

DCR supports pre-build and post-build steps:

• build.steps — commands before compilation
• build.post_steps — commands after compilation

Substitutions: {stem}, {in}, {out}, {profile}, {version}, {name}.

Example Qt codegen via build steps:

[build.steps]
moc = "moc {in} -o {out}"

pkg-config

Automatic lookup (read from raw config):

[build]
pkg_config = ["sdl2", "gl"]

DCR runs pkg-config --cflags sdl2 gl and pkg-config --libs sdl2 gl and adds results to compiler/linker flags.

Variable Substitution

Supported variables:

Variable	Description
{version}	Package version
{version_major}	Major version part
{version_minor}	Minor version part
{version_patch}	Patch version
{version_suffix}	Suffix (e.g., -rc1)
{version_suffix_dash}	Suffix with dash
{profile}	Profile name (debug/release)
{name}	Package name