Add support for versioned stubs.
A cc_library or cc_library_shared can be configured to have stubs
variants of the lib.
cc_library_shared {
name: "libfoo",
srcs: ["foo.cpp"],
stubs: {
symbol_file: "foo.map.txt",
versions: ["1", "2", "3"],
},
}
then, stubs variants of libfoo for version 1, 2, and 3 are created
from foo.map.txt. Each version has the symbols from the map file where
each symbol is annotated with the version that the symbol was introduced
via the 'introduced=<ver>' syntax. The versions don't need to be in sync
with the platform versions (e.g., P for 28). The versions are local to
the library.
For another library or executable to use the versioned stubs lib, use
the new 'name#ver' syntax to specify the version:
cc_binary {
name: "test",
....
shared_libs: ["libFoo#2"],
}
Internally, a new mutator 'version' is applied to all cc.Module objects.
By default, a variant named 'impl' is created for the non-stub version.
If the versions property is set, additional variations are created per a
version with the mutable property BuildStubs set as true, which lets the
compiler and the linker to build a stubs lib from the symbol file
instead from the source files.
This feature will be used to enforce stable interfaces among APEXs. When
a lib foo in an APEX is depending on a lib bar in another APEX, then bar
should have stable interface (in C lang) and foo should be depending on
one of the stubs libs of bar. Only libraries in the same APEX as foo can
link against non-stub version of it.
Bug: 112672359
Test: m (cc_test added)
Change-Id: I2488be0b9d7b7b8d7761234dc1c9c0e3add8601c
diff --git a/cc/linker.go b/cc/linker.go
index 28f4747..e96bfcb 100644
--- a/cc/linker.go
+++ b/cc/linker.go
@@ -160,7 +160,8 @@
Properties BaseLinkerProperties
MoreProperties MoreBaseLinkerProperties
dynamicProperties struct {
- RunPaths []string `blueprint:"mutated"`
+ RunPaths []string `blueprint:"mutated"`
+ BuildStubs bool `blueprint:"mutated"`
}
sanitize *sanitize
@@ -269,9 +270,13 @@
deps.LateStaticLibs = append(deps.LateStaticLibs, "libwinpthread")
}
- android.ExtractSourceDeps(ctx, linker.MoreProperties.Version_script)
- android.ExtractSourceDeps(ctx,
- linker.MoreProperties.Target.Vendor.Version_script)
+ // Version_script is not needed when linking stubs lib where the version
+ // script is created from the symbol map file.
+ if !linker.dynamicProperties.BuildStubs {
+ android.ExtractSourceDeps(ctx, linker.MoreProperties.Version_script)
+ android.ExtractSourceDeps(ctx,
+ linker.MoreProperties.Target.Vendor.Version_script)
+ }
return deps
}
@@ -375,28 +380,32 @@
flags.GroupStaticLibs = true
}
- versionScript := ctx.ExpandOptionalSource(
- linker.MoreProperties.Version_script, "version_script")
+ // Version_script is not needed when linking stubs lib where the version
+ // script is created from the symbol map file.
+ if !linker.dynamicProperties.BuildStubs {
+ versionScript := ctx.ExpandOptionalSource(
+ linker.MoreProperties.Version_script, "version_script")
- if ctx.useVndk() && linker.MoreProperties.Target.Vendor.Version_script != nil {
- versionScript = ctx.ExpandOptionalSource(
- linker.MoreProperties.Target.Vendor.Version_script,
- "target.vendor.version_script")
- }
+ if ctx.useVndk() && linker.MoreProperties.Target.Vendor.Version_script != nil {
+ versionScript = ctx.ExpandOptionalSource(
+ linker.MoreProperties.Target.Vendor.Version_script,
+ "target.vendor.version_script")
+ }
- if versionScript.Valid() {
- if ctx.Darwin() {
- ctx.PropertyErrorf("version_script", "Not supported on Darwin")
- } else {
- flags.LdFlags = append(flags.LdFlags,
- "-Wl,--version-script,"+versionScript.String())
- flags.LdFlagsDeps = append(flags.LdFlagsDeps, versionScript.Path())
-
- if linker.sanitize.isSanitizerEnabled(cfi) {
- cfiExportsMap := android.PathForSource(ctx, cfiExportsMapPath)
+ if versionScript.Valid() {
+ if ctx.Darwin() {
+ ctx.PropertyErrorf("version_script", "Not supported on Darwin")
+ } else {
flags.LdFlags = append(flags.LdFlags,
- "-Wl,--version-script,"+cfiExportsMap.String())
- flags.LdFlagsDeps = append(flags.LdFlagsDeps, cfiExportsMap)
+ "-Wl,--version-script,"+versionScript.String())
+ flags.LdFlagsDeps = append(flags.LdFlagsDeps, versionScript.Path())
+
+ if linker.sanitize.isSanitizerEnabled(cfi) {
+ cfiExportsMap := android.PathForSource(ctx, cfiExportsMapPath)
+ flags.LdFlags = append(flags.LdFlags,
+ "-Wl,--version-script,"+cfiExportsMap.String())
+ flags.LdFlagsDeps = append(flags.LdFlagsDeps, cfiExportsMap)
+ }
}
}
}