Merge "Reland: Fix -Wl,--exclude-libs for clang runtime libraries" am: e11164351a

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2130354

Change-Id: I1210e4e11d23bf86007fa28abdbbca93d892ee3a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

cc/cc.go

@@ -95,6 +95,10 @@ type Deps struct {
 	HeaderLibs                                  []string
 	RuntimeLibs                                 []string
 
+	// UnexportedStaticLibs are static libraries that are also passed to -Wl,--exclude-libs= to
+	// prevent automatically exporting symbols.
+	UnexportedStaticLibs []string
+
 	// Used for data dependencies adjacent to tests
 	DataLibs []string
 	DataBins []string
@@ -156,6 +160,7 @@ type PathDeps struct {
 	GeneratedDeps    android.Paths
 
 	Flags                      []string
+	LdFlags                    []string
 	IncludeDirs                android.Paths
 	SystemIncludeDirs          android.Paths
 	ReexportedDirs             android.Paths
@@ -678,6 +683,9 @@ type libraryDependencyTag struct {
 
 	// Whether or not this dependency has to be followed for the apex variants
 	excludeInApex bool
+
+	// If true, don't automatically export symbols from the static library into a shared library.
+	unexportedSymbols bool
 }
 
 // header returns true if the libraryDependencyTag is tagging a header lib dependency.
@@ -1921,6 +1929,8 @@ func (c *Module) GenerateAndroidBuildActions(actx android.ModuleContext) {
 		flags.Local.CommonFlags = append(flags.Local.CommonFlags, "-isystem "+dir.String())
 	}
 
+	flags.Local.LdFlags = append(flags.Local.LdFlags, deps.LdFlags...)
+
 	c.flags = flags
 	// We need access to all the flags seen by a source file.
 	if c.sabi != nil {
@@ -2368,6 +2378,13 @@ func (c *Module) DepsMutator(actx android.BottomUpMutatorContext) {
 		}, depTag, RewriteSnapshotLib(lib, GetSnapshot(c, &snapshotInfo, actx).StaticLibs))
 	}
 
+	for _, lib := range deps.UnexportedStaticLibs {
+		depTag := libraryDependencyTag{Kind: staticLibraryDependency, Order: lateLibraryDependency, unexportedSymbols: true}
+		actx.AddVariationDependencies([]blueprint.Variation{
+			{Mutator: "link", Variation: "static"},
+		}, depTag, RewriteSnapshotLib(lib, GetSnapshot(c, &snapshotInfo, actx).StaticLibs))
+	}
+
 	for _, lib := range deps.LateSharedLibs {
 		if inList(lib, sharedLibNames) {
 			// This is to handle the case that some of the late shared libs (libc, libdl, libm, ...)
@@ -2866,6 +2883,10 @@ func (c *Module) depsToPaths(ctx android.ModuleContext) PathDeps {
 						panic(fmt.Errorf("unexpected library dependency order %d", libDepTag.Order))
 					}
 				}
+				if libDepTag.unexportedSymbols {
+					depPaths.LdFlags = append(depPaths.LdFlags,
+						"-Wl,--exclude-libs="+staticLibraryInfo.StaticLibrary.Base())
+				}
 			}
 
 			if libDepTag.static() && !libDepTag.wholeStatic {

cc/linker.go

@@ -399,7 +399,7 @@ func (linker *baseLinker) linkerDeps(ctx DepsContext, deps Deps) Deps {
 	if ctx.toolchain().Bionic() {
 		// libclang_rt.builtins has to be last on the command line
 		if !Bool(linker.Properties.No_libcrt) && !ctx.header() {
-			deps.LateStaticLibs = append(deps.LateStaticLibs, config.BuiltinsRuntimeLibrary(ctx.toolchain()))
+			deps.UnexportedStaticLibs = append(deps.UnexportedStaticLibs, config.BuiltinsRuntimeLibrary(ctx.toolchain()))
 		}
 
 		if inList("libdl", deps.SharedLibs) {
@@ -422,7 +422,7 @@ func (linker *baseLinker) linkerDeps(ctx DepsContext, deps Deps) Deps {
 		}
 	} else if ctx.toolchain().Musl() {
 		if !Bool(linker.Properties.No_libcrt) && !ctx.header() {
-			deps.LateStaticLibs = append(deps.LateStaticLibs, config.BuiltinsRuntimeLibrary(ctx.toolchain()))
+			deps.UnexportedStaticLibs = append(deps.UnexportedStaticLibs, config.BuiltinsRuntimeLibrary(ctx.toolchain()))
 		}
 	}
 
@@ -530,10 +530,6 @@ func (linker *baseLinker) linkerFlags(ctx ModuleContext, flags Flags) Flags {
 		}
 	}
 
-	if ctx.toolchain().LibclangRuntimeLibraryArch() != "" {
-		flags.Global.LdFlags = append(flags.Global.LdFlags, "-Wl,--exclude-libs="+config.BuiltinsRuntimeLibrary(ctx.toolchain())+".a")
-	}
-
 	CheckBadLinkerFlags(ctx, "ldflags", linker.Properties.Ldflags)
 
 	flags.Local.LdFlags = append(flags.Local.LdFlags, proptools.NinjaAndShellEscapeList(linker.Properties.Ldflags)...)

cc/sanitize.go

@@ -588,13 +588,6 @@ func toDisableUnsignedShiftBaseChange(flags []string) bool {
 }
 
 func (sanitize *sanitize) flags(ctx ModuleContext, flags Flags) Flags {
-	minimalRuntimeLib := config.UndefinedBehaviorSanitizerMinimalRuntimeLibrary(ctx.toolchain()) + ".a"
-
-	if sanitize.Properties.MinimalRuntimeDep {
-		flags.Local.LdFlags = append(flags.Local.LdFlags,
-			"-Wl,--exclude-libs,"+minimalRuntimeLib)
-	}
-
 	if !sanitize.Properties.SanitizerEnabled && !sanitize.Properties.UbsanRuntimeDep {
 		return flags
 	}
@@ -724,7 +717,6 @@ func (sanitize *sanitize) flags(ctx ModuleContext, flags Flags) Flags {
 
 		if enableMinimalRuntime(sanitize) {
 			flags.Local.CFlags = append(flags.Local.CFlags, strings.Join(minimalRuntimeFlags, " "))
-			flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,--exclude-libs,"+minimalRuntimeLib)
 		}
 
 		if Bool(sanitize.Properties.Sanitize.Fuzzer) {
@@ -1217,7 +1209,7 @@ func sanitizerRuntimeMutator(mctx android.BottomUpMutatorContext) {
 			}
 
 			// static executable gets static runtime libs
-			depTag := libraryDependencyTag{Kind: staticLibraryDependency}
+			depTag := libraryDependencyTag{Kind: staticLibraryDependency, unexportedSymbols: true}
 			variations := append(mctx.Target().Variations(),
 				blueprint.Variation{Mutator: "link", Variation: "static"})
 			if c.Device() {

cc/sanitize_test.go

@@ -16,6 +16,7 @@ package cc
 
 import (
 	"fmt"
+	"runtime"
 	"strings"
 	"testing"
 
@@ -201,6 +202,125 @@ func TestAsan(t *testing.T) {
 	t.Run("device", func(t *testing.T) { check(t, result, "android_arm64_armv8-a") })
 }
 
+func TestUbsan(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip("requires linux")
+	}
+
+	bp := `
+		cc_binary {
+			name: "bin_with_ubsan",
+			host_supported: true,
+			shared_libs: [
+				"libshared",
+			],
+			static_libs: [
+				"libstatic",
+				"libnoubsan",
+			],
+			sanitize: {
+				undefined: true,
+			}
+		}
+
+		cc_binary {
+			name: "bin_depends_ubsan",
+			host_supported: true,
+			shared_libs: [
+				"libshared",
+			],
+			static_libs: [
+				"libstatic",
+				"libubsan",
+				"libnoubsan",
+			],
+		}
+
+		cc_binary {
+			name: "bin_no_ubsan",
+			host_supported: true,
+			shared_libs: [
+				"libshared",
+			],
+			static_libs: [
+				"libstatic",
+				"libnoubsan",
+			],
+		}
+
+		cc_library_shared {
+			name: "libshared",
+			host_supported: true,
+			shared_libs: ["libtransitive"],
+		}
+
+		cc_library_shared {
+			name: "libtransitive",
+			host_supported: true,
+		}
+
+		cc_library_static {
+			name: "libubsan",
+			host_supported: true,
+			sanitize: {
+				undefined: true,
+			}
+		}
+
+		cc_library_static {
+			name: "libstatic",
+			host_supported: true,
+		}
+
+		cc_library_static {
+			name: "libnoubsan",
+			host_supported: true,
+		}
+	`
+
+	result := android.GroupFixturePreparers(
+		prepareForCcTest,
+	).RunTestWithBp(t, bp)
+
+	check := func(t *testing.T, result *android.TestResult, variant string) {
+		staticVariant := variant + "_static"
+
+		minimalRuntime := result.ModuleForTests("libclang_rt.ubsan_minimal", staticVariant)
+
+		// The binaries, one with ubsan and one without
+		binWithUbsan := result.ModuleForTests("bin_with_ubsan", variant)
+		binDependsUbsan := result.ModuleForTests("bin_depends_ubsan", variant)
+		binNoUbsan := result.ModuleForTests("bin_no_ubsan", variant)
+
+		android.AssertStringListContains(t, "missing libclang_rt.ubsan_minimal in bin_with_ubsan static libs",
+			strings.Split(binWithUbsan.Rule("ld").Args["libFlags"], " "),
+			minimalRuntime.OutputFiles(t, "")[0].String())
+
+		android.AssertStringListContains(t, "missing libclang_rt.ubsan_minimal in bin_depends_ubsan static libs",
+			strings.Split(binDependsUbsan.Rule("ld").Args["libFlags"], " "),
+			minimalRuntime.OutputFiles(t, "")[0].String())
+
+		android.AssertStringListDoesNotContain(t, "unexpected libclang_rt.ubsan_minimal in bin_no_ubsan static libs",
+			strings.Split(binNoUbsan.Rule("ld").Args["libFlags"], " "),
+			minimalRuntime.OutputFiles(t, "")[0].String())
+
+		android.AssertStringListContains(t, "missing -Wl,--exclude-libs for minimal runtime in bin_with_ubsan",
+			strings.Split(binWithUbsan.Rule("ld").Args["ldFlags"], " "),
+			"-Wl,--exclude-libs="+minimalRuntime.OutputFiles(t, "")[0].Base())
+
+		android.AssertStringListContains(t, "missing -Wl,--exclude-libs for minimal runtime in bin_depends_ubsan static libs",
+			strings.Split(binDependsUbsan.Rule("ld").Args["ldFlags"], " "),
+			"-Wl,--exclude-libs="+minimalRuntime.OutputFiles(t, "")[0].Base())
+
+		android.AssertStringListDoesNotContain(t, "unexpected -Wl,--exclude-libs for minimal runtime in bin_no_ubsan static libs",
+			strings.Split(binNoUbsan.Rule("ld").Args["ldFlags"], " "),
+			"-Wl,--exclude-libs="+minimalRuntime.OutputFiles(t, "")[0].Base())
+	}
+
+	t.Run("host", func(t *testing.T) { check(t, result, result.Config.BuildOSTarget.String()) })
+	t.Run("device", func(t *testing.T) { check(t, result, "android_arm64_armv8-a") })
+}
+
 type MemtagNoteType int
 
 const (

cc/testing.go

@@ -73,7 +73,6 @@ func commonDefaultModules() string {
 			nocrt: true,
 			system_shared_libs: [],
 			stl: "none",
-			srcs: [""],
 			check_elf_files: false,
 			sanitize: {
 				never: true,
@@ -84,6 +83,7 @@ func commonDefaultModules() string {
 			name: "libcompiler_rt-extras",
 			defaults: ["toolchain_libs_defaults"],
 			vendor_ramdisk_available: true,
+			srcs: [""],
 		}
 
 		cc_prebuilt_library_static {
@@ -93,11 +93,13 @@ func commonDefaultModules() string {
 	        vendor_available: true,
 			vendor_ramdisk_available: true,
 			native_bridge_supported: true,
+			srcs: [""],
 		}
 
 		cc_prebuilt_library_shared {
 			name: "libclang_rt.hwasan",
 			defaults: ["toolchain_libs_defaults"],
+			srcs: [""],
 		}
 
 		cc_prebuilt_library_static {
@@ -108,6 +110,7 @@ func commonDefaultModules() string {
 			],
 			vendor_ramdisk_available: true,
 			native_bridge_supported: true,
+			srcs: [""],
 		}
 
 		cc_prebuilt_library_static {
@@ -116,17 +119,34 @@ func commonDefaultModules() string {
 				"linux_bionic_supported",
 				"toolchain_libs_defaults",
 			],
+			srcs: [""],
 		}
 
 		// Needed for sanitizer
 		cc_prebuilt_library_shared {
 			name: "libclang_rt.ubsan_standalone",
 			defaults: ["toolchain_libs_defaults"],
+			srcs: [""],
 		}
 
 		cc_prebuilt_library_static {
 			name: "libclang_rt.ubsan_minimal",
 			defaults: ["toolchain_libs_defaults"],
+			host_supported: true,
+			target: {
+				android_arm64: {
+					srcs: ["libclang_rt.ubsan_minimal.android_arm64.a"],
+				},
+				android_arm: {
+					srcs: ["libclang_rt.ubsan_minimal.android_arm.a"],
+				},
+				linux_glibc_x86_64: {
+					srcs: ["libclang_rt.ubsan_minimal.x86_64.a"],
+				},
+				linux_glibc_x86: {
+					srcs: ["libclang_rt.ubsan_minimal.x86.a"],
+				},
+			},
 		}
 
 		cc_library {
@@ -546,6 +566,11 @@ var PrepareForTestWithCcDefaultModules = android.GroupFixturePreparers(
 		"defaults/cc/common/crtend_so.c":            nil,
 		"defaults/cc/common/crtend.c":               nil,
 		"defaults/cc/common/crtbrand.c":             nil,
+
+		"defaults/cc/common/libclang_rt.ubsan_minimal.android_arm64.a": nil,
+		"defaults/cc/common/libclang_rt.ubsan_minimal.android_arm.a":   nil,
+		"defaults/cc/common/libclang_rt.ubsan_minimal.x86_64.a":        nil,
+		"defaults/cc/common/libclang_rt.ubsan_minimal.x86.a":           nil,
 	}.AddToFixture(),
 
 	// Place the default cc test modules that are common to all platforms in a location that will not