Add USE_CLANG_LLD and use_clang_lld.
* USE_CLANG_LLD is unedefined in current builds.
* When USE_CLANG_LLD is defined to 'true' or '1',
use clang's lld instead of ld or ld.gold.
* When lld is enabled:
* ld-only flags are not passed to 'lld'.
* location_packer is disabled.
* Use new lld's --pack-dyn-relocs=android.
* When lld does not work:
* In Android.mk files use LOCAL_USE_CLANG_LLD := false.
* In Android.bp files use use_clang_lld: false.
* Only arm, arm64, x86, and x86_64_devices have LLD flags;
all other hosts and targets do not call lld yet.
Bug: 73768157
Test: make checkbuild and boot
Change-Id: I06b8a1e868a600997a7e70fe05c299d751d23d5f
diff --git a/cc/linker.go b/cc/linker.go
index bcedc8d..2176306 100644
--- a/cc/linker.go
+++ b/cc/linker.go
@@ -58,6 +58,9 @@
// don't link in libgcc.a
No_libgcc *bool
+ // Use clang lld instead of gnu ld.
+ Use_clang_lld *bool
+
// -l arguments to pass to linker for host-provided shared libraries
Host_ldlibs []string `android:"arch_variant"`
@@ -201,6 +204,15 @@
return deps
}
+func (linker *baseLinker) useClangLld(ctx ModuleContext) bool {
+ if linker.Properties.Use_clang_lld != nil {
+ return Bool(linker.Properties.Use_clang_lld)
+ }
+ return ctx.Config().UseClangLld()
+}
+
+// ModuleContext extends BaseModuleContext
+// BaseModuleContext should know if LLD is used?
func (linker *baseLinker) linkerFlags(ctx ModuleContext, flags Flags) Flags {
toolchain := ctx.toolchain()
@@ -209,7 +221,11 @@
hod = "Device"
}
- flags.LdFlags = append(flags.LdFlags, fmt.Sprintf("${config.%sGlobalLdflags}", hod))
+ if flags.Clang && linker.useClangLld(ctx) {
+ flags.LdFlags = append(flags.LdFlags, fmt.Sprintf("${config.%sGlobalLldflags}", hod))
+ } else {
+ flags.LdFlags = append(flags.LdFlags, fmt.Sprintf("${config.%sGlobalLdflags}", hod))
+ }
if Bool(linker.Properties.Allow_undefined_symbols) {
if ctx.Darwin() {
// darwin defaults to treating undefined symbols as errors
@@ -219,7 +235,9 @@
flags.LdFlags = append(flags.LdFlags, "-Wl,--no-undefined")
}
- if flags.Clang {
+ if flags.Clang && linker.useClangLld(ctx) {
+ flags.LdFlags = append(flags.LdFlags, toolchain.ClangLldflags())
+ } else if flags.Clang {
flags.LdFlags = append(flags.LdFlags, toolchain.ClangLdflags())
} else {
flags.LdFlags = append(flags.LdFlags, toolchain.Ldflags())