Ensure hermetic device rust_bindgen.

rust_bindgen was not hermetic previously as it would pull in host
headers for device targets. This fixes that by using the same flags we
use when compiling with Clang. This also makes sure our rust_bindgen
headers are built as similar as possible to their respective
cc_libraries.

This also pulls in the bionic dependencies as well, which provide the
headers required for device targets.

Bug: 162007475
Test: device rust_bindgen deps file does not reference host headers.

Change-Id: I4efdf333e011a6c6d73a0345e5485823f166d17a

1 files changed, 30 insertions, 27 deletions

diff --git a/rust/bindgen.go b/rust/bindgen.go
index 099bc6e26..43053b02b 100644
--- a/rust/bindgen.go
+++ b/rust/bindgen.go
@@ -15,11 +15,11 @@
 package rust
 
 import (
-	"github.com/google/blueprint"
 	"strings"
 
+	"github.com/google/blueprint"
+
 	"android/soong/android"
-	"android/soong/cc"
 	ccConfig "android/soong/cc/config"
 )
 
@@ -84,40 +84,39 @@ type bindgenDecorator struct {
 	Properties BindgenProperties
 }
 
-func (b *bindgenDecorator) libraryExports(ctx android.ModuleContext) (android.Paths, []string) {
-	var libraryPaths android.Paths
-	var libraryFlags []string
+func (b *bindgenDecorator) generateSource(ctx android.ModuleContext, deps PathDeps) android.Path {
+	ccToolchain := ccConfig.FindToolchain(ctx.Os(), ctx.Arch())
 
-	for _, static_lib := range b.Properties.Static_libs {
-		if dep, ok := ctx.GetDirectDepWithTag(static_lib, cc.StaticDepTag).(*cc.Module); ok {
-			libraryPaths = append(libraryPaths, dep.ExportedIncludeDirs()...)
-			libraryFlags = append(libraryFlags, dep.ExportedFlags()...)
-		}
-	}
-	for _, shared_lib := range b.Properties.Shared_libs {
-		if dep, ok := ctx.GetDirectDepWithTag(shared_lib, cc.SharedDepTag).(*cc.Module); ok {
-			libraryPaths = append(libraryPaths, dep.ExportedIncludeDirs()...)
-			libraryFlags = append(libraryFlags, dep.ExportedFlags()...)
-		}
-	}
+	var cflags []string
+	var implicits android.Paths
 
-	return libraryPaths, libraryFlags
-}
+	implicits = append(implicits, deps.depIncludePaths...)
+	implicits = append(implicits, deps.depSystemIncludePaths...)
 
-func (b *bindgenDecorator) generateSource(ctx android.ModuleContext) android.Path {
-	ccToolchain := ccConfig.FindToolchain(ctx.Os(), ctx.Arch())
-	includes, exportedFlags := b.libraryExports(ctx)
+	// Default clang flags
+	cflags = append(cflags, "${ccConfig.CommonClangGlobalCflags}")
+	if ctx.Device() {
+		cflags = append(cflags, "${ccConfig.DeviceClangGlobalCflags}")
+	}
 
-	var cflags []string
-	cflags = append(cflags, b.Properties.Cflags...)
+	// Toolchain clang flags
 	cflags = append(cflags, "-target "+ccToolchain.ClangTriple())
 	cflags = append(cflags, strings.ReplaceAll(ccToolchain.ToolchainClangCflags(), "${config.", "${ccConfig."))
-	cflags = append(cflags, exportedFlags...)
-	for _, include := range includes {
+
+	// Dependency clang flags and include paths
+	cflags = append(cflags, deps.depClangFlags...)
+	for _, include := range deps.depIncludePaths {
 		cflags = append(cflags, "-I"+include.String())
 	}
+	for _, include := range deps.depSystemIncludePaths {
+		cflags = append(cflags, "-isystem "+include.String())
+	}
+
+	// Module defined clang flags and include paths
+	cflags = append(cflags, b.Properties.Cflags...)
 	for _, include := range b.Properties.Local_include_dirs {
 		cflags = append(cflags, "-I"+android.PathForModuleSrc(ctx, include).String())
+		implicits = append(implicits, android.PathForModuleSrc(ctx, include))
 	}
 
 	bindgenFlags := defaultBindgenFlags
@@ -135,7 +134,7 @@ func (b *bindgenDecorator) generateSource(ctx android.ModuleContext) android.Pat
 		Description: "bindgen " + wrapperFile.Path().Rel(),
 		Output:      outputFile,
 		Input:       wrapperFile.Path(),
-		Implicits:   includes,
+		Implicits:   implicits,
 		Args: map[string]string{
 			"flags":  strings.Join(bindgenFlags, " "),
 			"cflags": strings.Join(cflags, " "),
@@ -172,6 +171,10 @@ func NewRustBindgen(hod android.HostOrDeviceSupported) (*Module, *bindgenDecorat
 
 func (b *bindgenDecorator) sourceProviderDeps(ctx DepsContext, deps Deps) Deps {
 	deps = b.baseSourceProvider.sourceProviderDeps(ctx, deps)
+	if ctx.toolchain().Bionic() {
+		deps = bionicDeps(deps)
+	}
+
 	deps.SharedLibs = append(deps.SharedLibs, b.Properties.Shared_libs...)
 	deps.StaticLibs = append(deps.StaticLibs, b.Properties.Static_libs...)
 	return deps