Re-introduce ccache support (#863)
Recent change 9a4ba8138aed94000ac5070590a21030008903bb removed ccache
support from the build process. This commit re-introduces ccache support
and updates GN files accordingly. Since ccache only supports
compilation, updates have been made to the compiler prefixes.
Additionally, assertions have been added to ensure ccache is not used on
Windows or in conjunction with RBE.
Fixes https://github.com/flutter/flutter/issues/149100
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advice.
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- [x] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
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diff --git a/build/toolchain/android/BUILD.gn b/build/toolchain/android/BUILD.gn
index af1243f..bbce14b 100644
--- a/build/toolchain/android/BUILD.gn
+++ b/build/toolchain/android/BUILD.gn
@@ -3,6 +3,7 @@
# found in the LICENSE file.
import("//build/config/sysroot.gni") # Imports android/config.gni.
+import("//build/toolchain/ccache.gni")
import("//build/toolchain/clang.gni")
import("//build/toolchain/gcc_toolchain.gni")
import("//build/toolchain/rbe.gni")
@@ -56,6 +57,11 @@
assembler_prefix = ""
compiler_prefix = string_join(" ", compiler_args)
link_prefix = ""
+ } else if (use_ccache) {
+ # ccache only supports compilation, not linking.
+ assembler_prefix = "ccache "
+ compiler_prefix = ""
+ link_prefix = ""
} else {
compiler_prefix = ""
link_prefix = ""
diff --git a/build/toolchain/ccache.gni b/build/toolchain/ccache.gni
index 806e079..e3a848c 100644
--- a/build/toolchain/ccache.gni
+++ b/build/toolchain/ccache.gni
@@ -19,7 +19,12 @@
# speed, you can do:
# export CCACHE_CPP2=yes
+import("//build/toolchain/rbe.gni") # for use_rbe
+
declare_args() {
# Set to true to enable ccache. Probably doesn't work on windows.
use_ccache = false
}
+
+assert(!is_win || !use_ccache, "ccache is not supported on Windows")
+assert(!use_ccache || !use_rbe, "ccache is not supported with RBE")
diff --git a/build/toolchain/fuchsia/BUILD.gn b/build/toolchain/fuchsia/BUILD.gn
index 4d47099..729001c 100644
--- a/build/toolchain/fuchsia/BUILD.gn
+++ b/build/toolchain/fuchsia/BUILD.gn
@@ -4,6 +4,7 @@
import("//build/toolchain/clang.gni")
import("//build/toolchain/rbe.gni")
+import("//build/toolchain/ccache.gni")
import("//build/toolchain/toolchain.gni")
if (use_rbe) {
@@ -11,6 +12,10 @@
rewrapper_command + [ "--labels=type=compile,compiler=clang,lang=cpp " ]
compiler_prefix = string_join(" ", compiler_args)
link_prefix = ""
+} else if (use_ccache) {
+ # ccache only supports compilation, not linking.
+ compiler_prefix = "ccache"
+ link_prefix = ""
} else {
compiler_prefix = ""
link_prefix = ""
diff --git a/build/toolchain/linux/BUILD.gn b/build/toolchain/linux/BUILD.gn
index d5c2ca3..3d603a0 100644
--- a/build/toolchain/linux/BUILD.gn
+++ b/build/toolchain/linux/BUILD.gn
@@ -3,6 +3,7 @@
# found in the LICENSE file.
import("//build/config/sysroot.gni")
+import("//build/toolchain/ccache.gni")
import("//build/toolchain/gcc_toolchain.gni")
import("//build/toolchain/rbe.gni")
import("//build/toolchain/toolchain.gni")
@@ -23,6 +24,10 @@
]
compiler_prefix = string_join(" ", compiler_args)
link_prefix = ""
+} else if (use_ccache) {
+ # ccache only supports compilation, not linking.
+ compiler_prefix = "ccache "
+ link_prefix = ""
} else {
compiler_prefix = ""
link_prefix = ""
diff --git a/build/toolchain/mac/BUILD.gn b/build/toolchain/mac/BUILD.gn
index 9e507cd..7e9db05 100644
--- a/build/toolchain/mac/BUILD.gn
+++ b/build/toolchain/mac/BUILD.gn
@@ -10,6 +10,7 @@
import("//build/toolchain/clang.gni")
import("//build/toolchain/clang_static_analyzer.gni")
import("//build/toolchain/rbe.gni")
+import("//build/toolchain/ccache.gni")
import("//build/toolchain/toolchain.gni")
if (host_cpu == "arm64") {
@@ -20,7 +21,12 @@
rebase_path("$buildtools_path/mac-x64/clang/bin", root_build_dir)
}
-if (use_rbe) {
+if (use_ccache) {
+ # ccache only supports compilation, not linking.
+ cxx_prefix = "ccache "
+ objc_prefix = "ccache "
+ link_prefix = ""
+} else if (use_rbe) {
remote_wrapper =
rebase_path("//flutter/build/rbe/remote_wrapper.sh", root_build_dir)
local_wrapper =
diff --git a/build/toolchain/wasm.gni b/build/toolchain/wasm.gni
index 0d9e3bf..1e4b953 100644
--- a/build/toolchain/wasm.gni
+++ b/build/toolchain/wasm.gni
@@ -17,6 +17,13 @@
em_config_path = "$emsdk_dir/.emscripten"
+if (use_ccache) {
+ # ccache only supports compilation, not linking.
+ compiler_prefix = "ccache "
+} else {
+ compiler_prefix = ""
+}
+
template("wasm_toolchain") {
gcc_toolchain(target_name) {
extra_toolchain_args = {
@@ -27,9 +34,9 @@
# emsdk_dir and em_config are defined in wasm.gni.
ar = "$emsdk_dir/upstream/emscripten/emar --em-config $em_config_path"
- cc = "$emsdk_dir/upstream/emscripten/emcc --em-config $em_config_path"
- cxx = "$emsdk_dir/upstream/emscripten/em++ --em-config $em_config_path"
- asm = cc
+ cc = "$compiler_prefix$emsdk_dir/upstream/emscripten/emcc --em-config $em_config_path"
+ cxx = "$compiler_prefix$emsdk_dir/upstream/emscripten/em++ --em-config $em_config_path"
+ asm = "$emsdk_dir/upstream/emscripten/emcc --em-config $em_config_path"
# emscripten emits this .worker.js file conditionally depending on whether
# pthreads are on or not. Unfortunately, there is no way to conditionally
@@ -39,7 +46,7 @@
# dummy file. If the target does use pthreads, this dummy file will be
# overwritten. If the target does not, the dummy file will satisfy the
# toolchain's requirement that it has this as an output.
- ld = "$cxx"
+ ld = "$emsdk_dir/upstream/emscripten/em++ --em-config $em_config_path"
readelf = "readelf"
nm = "nm"
