platform_build_soong/cc/toolchain_library.go
Yi Kong acee27cd72 Strip libgcc to only keep fallback symbols
We use libgcc as fallback for symbols not present in libclang_rt
builtins, however we didn't know what exact symbols were being used,
some may not be intended to fallback.

Create libgcc_stripped, which only contains unwind symbols from libgcc.

Bug: 29275768
Test: bionic-unit-tests
Change-Id: I5b349fa6138e51663bf3b67109b880b4356da8e8
2019-04-30 10:07:00 -07:00

98 lines
2.8 KiB
Go

// Copyright 2016 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package cc
import (
"android/soong/android"
)
//
// Device libraries shipped with gcc
//
func init() {
android.RegisterModuleType("toolchain_library", ToolchainLibraryFactory)
}
type toolchainLibraryProperties struct {
// the prebuilt toolchain library, as a path from the top of the source tree
Src *string `android:"arch_variant"`
}
type toolchainLibraryDecorator struct {
*libraryDecorator
stripper
Properties toolchainLibraryProperties
}
func (*toolchainLibraryDecorator) linkerDeps(ctx DepsContext, deps Deps) Deps {
// toolchain libraries can't have any dependencies
return deps
}
func (library *toolchainLibraryDecorator) linkerProps() []interface{} {
var props []interface{}
props = append(props, library.libraryDecorator.linkerProps()...)
return append(props, &library.Properties, &library.stripper.StripProperties)
}
// toolchain_library is used internally by the build tool to link the specified
// static library in src property to the device libraries that are shipped with
// gcc.
func ToolchainLibraryFactory() android.Module {
module, library := NewLibrary(android.HostAndDeviceSupported)
library.BuildOnlyStatic()
toolchainLibrary := &toolchainLibraryDecorator{
libraryDecorator: library,
}
module.compiler = toolchainLibrary
module.linker = toolchainLibrary
module.stl = nil
module.sanitize = nil
module.installer = nil
return module.Init()
}
func (library *toolchainLibraryDecorator) compile(ctx ModuleContext, flags Flags,
deps PathDeps) Objects {
return Objects{}
}
func (library *toolchainLibraryDecorator) link(ctx ModuleContext,
flags Flags, deps PathDeps, objs Objects) android.Path {
if library.Properties.Src == nil {
ctx.PropertyErrorf("src", "No library source specified")
return android.PathForSource(ctx, "")
}
srcPath := android.PathForSource(ctx, *library.Properties.Src)
if library.stripper.StripProperties.Strip.Keep_symbols_list != nil {
fileName := ctx.ModuleName() + staticLibraryExtension
outputFile := android.PathForModuleOut(ctx, fileName)
buildFlags := flagsToBuilderFlags(flags)
library.stripper.strip(ctx, srcPath, outputFile, buildFlags)
return outputFile
}
return srcPath
}
func (library *toolchainLibraryDecorator) nativeCoverage() bool {
return false
}