Fix missing NOTICE targets for static libs that aren't available to

platform.

The NOTICE file generation depends on the NOTICE targets for all static
library dependencies. If such a dependency didn't have
//apex_available:platform it didn't get any AndroidMk entry and hence
no NOTICE target via soong_cc_prebuilt.mk. If it was then depended upon
by a binary or library that is accessible to platform, the NOTICE
dependency failed.

Normally such a dependency is invalid, but there are corner cases where
binaries go neither into platform nor any APEX module, and they can
legitimately have such dependencies (cf. b/152241137).

With this CL requests to skip installation of such a static libraries
are ignored so that they get AndroidMk entries, which will always have
LOCAL_UNINSTALLABLE_MODULE set.

Test: "m simpleperf_ndk" with https://r.android.com/1273016, which
  removes //apex_available:platform from libs that simpleperf_ndk
  depends on statically.
Bug: 152241137
Bug: 149217815
Change-Id: If36e85dd16ade56d4ec1d6744811df5a15b6242c

cc/androidmk.go

@@ -248,6 +248,10 @@ func (library *libraryDecorator) AndroidMkEntries(ctx AndroidMkContext, entries
 			entries.SubName = "." + library.stubsVersion()
 		}
 		entries.ExtraEntries = append(entries.ExtraEntries, func(entries *android.AndroidMkEntries) {
+			// Note library.skipInstall() has a special case to get here for static
+			// libraries that otherwise would have skipped installation and hence not
+			// have executed AndroidMkEntries at all. The reason is to ensure they get
+			// a NOTICE file make target which other libraries might depend on.
 			entries.SetBool("LOCAL_UNINSTALLABLE_MODULE", true)
 			if library.buildStubs() {
 				entries.SetBool("LOCAL_NO_NOTICE_FILE", true)

cc/cc.go

@@ -389,6 +389,7 @@ type installer interface {
 	inSanitizerDir() bool
 	hostToolPath() android.OptionalPath
 	relativeInstallPath() string
+	skipInstall(mod *Module)
 }
 
 type xref interface {
@@ -2590,6 +2591,14 @@ func (c *Module) InstallInRecovery() bool {
 	return c.InRecovery()
 }
 
+func (c *Module) SkipInstall() {
+	if c.installer == nil {
+		c.ModuleBase.SkipInstall()
+		return
+	}
+	c.installer.skipInstall(c)
+}
+
 func (c *Module) HostToolPath() android.OptionalPath {
 	if c.installer == nil {
 		return android.OptionalPath{}

cc/installer.go

@@ -106,3 +106,7 @@ func (installer *baseInstaller) hostToolPath() android.OptionalPath {
 func (installer *baseInstaller) relativeInstallPath() string {
 	return String(installer.Properties.Relative_install_path)
 }
+
+func (installer *baseInstaller) skipInstall(mod *Module) {
+	mod.ModuleBase.SkipInstall()
+}

cc/library.go

@@ -1329,6 +1329,18 @@ func (library *libraryDecorator) availableFor(what string) bool {
 	return android.CheckAvailableForApex(what, list)
 }
 
+func (library *libraryDecorator) skipInstall(mod *Module) {
+	if library.static() && library.buildStatic() && !library.buildStubs() {
+		// If we're asked to skip installation of a static library (in particular
+		// when it's not //apex_available:platform) we still want an AndroidMk entry
+		// for it to ensure we get the relevant NOTICE file targets (cf.
+		// notice_files.mk) that other libraries might depend on. AndroidMkEntries
+		// always sets LOCAL_UNINSTALLABLE_MODULE for these entries.
+		return
+	}
+	mod.ModuleBase.SkipInstall()
+}
+
 var versioningMacroNamesListKey = android.NewOnceKey("versioningMacroNamesList")
 
 func versioningMacroNamesList(config android.Config) *map[string]string {

cc/prebuilt.go

@@ -155,6 +155,10 @@ func (p *prebuiltLibraryLinker) disablePrebuilt() {
 	p.properties.Srcs = nil
 }
 
+func (p *prebuiltLibraryLinker) skipInstall(mod *Module) {
+	mod.ModuleBase.SkipInstall()
+}
+
 func NewPrebuiltLibrary(hod android.HostOrDeviceSupported) (*Module, *libraryDecorator) {
 	module, library := NewLibrary(hod)
 	module.compiler = nil
@@ -163,6 +167,7 @@ func NewPrebuiltLibrary(hod android.HostOrDeviceSupported) (*Module, *libraryDec
 		libraryDecorator: library,
 	}
 	module.linker = prebuilt
+	module.installer = prebuilt
 
 	module.AddProperties(&prebuilt.properties)