gecko-dev/client.mk
Mike Hommey 4e8e23f4e8 Bug 1729383 - Simplify the parallel build setup. r=firefox-build-system-reviewers,mhentges
Historically, client.mk was not invoked with -jn because it would create
race conditions, but that was actually mostly solved by the addition of
`.NOTPARALLEL` in bug 422986, although the mechanism of adding -jn via
`MOZ_MAKE_FLAGS` or `MOZ_PARALLEL_BUILD` has continued well past that.

Nowadays, client.mk is only invoked by mach (it will even bail out if
that's not the case) and only has one target (`build`) and no
dependencies.

This means we don't need to rely on `MOZ_PARALLEL_BUILD` to pass `-jn` in
some cases, and can just always invoke `make -f client.mk` with `-jn`, even
when we just want no parallelism, in which case we can use `-j1`.

This, in turn, allows to remove the extra allow_parallel argument to
`_run_make`, and only rely on `num_jobs`, and to remove some of the
multiple ways the `n` in `-jn` could be set.

Differential Revision: https://phabricator.services.mozilla.com/D124729
2021-09-08 00:10:22 +00:00

69 lines
2.0 KiB
Makefile

# -*- makefile -*-
# vim:set ts=8 sw=8 sts=8 noet:
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
# Defines main targets for driving the Firefox build system.
#
# This make file should not be invoked directly. Instead, use
# `mach` (likely `mach build`) for invoking the build system.
#
# Options:
# MOZ_OBJDIR - Destination object directory
# MOZ_MAKE_FLAGS - Flags to pass to $(MAKE)
#
#######################################################################
ifndef MACH
$(error client.mk must be used via `mach`. Try running \
`./mach $(firstword $(MAKECMDGOALS) $(.DEFAULT_GOAL))`)
endif
### Load mozconfig options
include $(OBJDIR)/.mozconfig-client-mk
### Set up make flags
ifdef MOZ_AUTOMATION
ifeq (4.0,$(firstword $(sort 4.0 $(MAKE_VERSION))))
MOZ_MAKE_FLAGS += --output-sync=line
endif
endif
MOZ_MAKE = $(MAKE) $(MOZ_MAKE_FLAGS) -C $(OBJDIR)
### Rules
# The default rule is build
build::
# In automation, manage an sccache daemon. The starting of the server
# needs to be in a make file so sccache inherits the jobserver.
ifdef MOZBUILD_MANAGE_SCCACHE_DAEMON
build::
# Terminate any sccache server that might still be around.
-$(MOZBUILD_MANAGE_SCCACHE_DAEMON) --stop-server > /dev/null 2>&1
# Start a new server, ensuring it gets the jobserver file descriptors
# from make (but don't use the + prefix when make -n is used, so that
# the command doesn't run in that case)
mkdir -p $(UPLOAD_PATH)
$(if $(findstring n,$(filter-out --%, $(MAKEFLAGS))),,+)env SCCACHE_LOG=sccache=debug SCCACHE_ERROR_LOG=$(UPLOAD_PATH)/sccache.log $(MOZBUILD_MANAGE_SCCACHE_DAEMON) --start-server
endif
### Build it
build::
+$(MOZ_MAKE)
ifdef MOZ_AUTOMATION
build::
+$(MOZ_MAKE) automation/build
endif
ifdef MOZBUILD_MANAGE_SCCACHE_DAEMON
build::
# Terminate sccache server. This prints sccache stats.
-$(MOZBUILD_MANAGE_SCCACHE_DAEMON) --stop-server
endif
.PHONY: \
build