dcr/docs/reference-and-help/flags-and-environment.md

Flags & environment

This page summarizes runtime flags and environment variables that affect DCR behavior.

Build/run flags

Used with dcr build and dcr run:

• --debug: select debug profile.
• --release: select release profile.
• --target <triple>: build for specified target (short names: linux, macos, windows, freebsd, openbsd, netbsd).
• --force: ignore incremental cache checks and rebuild.
• --clean: remove target/<profile> and build.clean paths before build.
• --verbose: print compiler/linker command lines to stderr.
• --workspace <name>: filter build to a specific workspace member.

Notes:

• Flags can be passed in any order.
• Duplicate profile flags are rejected.

Clean flags

Used with dcr clean:

• --debug / --release: clean only selected profile directory.
• --all: in workspace root, also clean all members.

Environment variables

Tool selection overrides:

• DCR_COMPILER (all languages)
• DCR_CC, DCR_CXX, DCR_AS, DCR_AR, DCR_LD

Diagnostics:

• DCR_DEBUG=1 enables verbose build logging.

Quick examples

# Force full release rebuild
dcr build --release --force

# Clean before debug run
dcr run --clean --debug

# Use custom compiler from env
DCR_CC=clang-18 dcr build --debug