Remove use of static libdexfile to avoid linking in ART internal code.

- Create a static library libunwindstack_no_dex without DEX support.
- Use it in libdebuggerd_handler_fallback, whose only use is in the
  linker, which shouldn't need that support.
- Use it in init_first_stage, which doesn't need DEX support either.
- Also need a libbacktrace_no_dex since it's in the dependency chain
  from init_first_stage to libunwindstack_no_dex.

Also restrict the *_no_dex libs and libdebuggerd_handler_fallback as
much as possible to avoid inadvertent use of these reduced
functionality libs.

Test: m init_first_stage on Cuttlefish
  where BOARD_BUILD_SYSTEM_ROOT_IMAGE=false
Test: m system_image com.android.runtime
Test: Build & boot
Test: atest linker-unit-tests libunwindstack_unit_test debuggerd_test
Bug: 142944931
Bug: 151466650
Change-Id: Iaacb29bfe602f3ca12a00a712e2a64c45ff0118b

debuggerd/Android.bp

@@ -103,9 +103,14 @@ cc_library_static {
     export_include_dirs: ["include"],
 }
 
-// Fallback implementation.
+// Fallback implementation, for use in the Bionic linker only.
 cc_library_static {
     name: "libdebuggerd_handler_fallback",
+    visibility: ["//bionic/linker"],
+    apex_available: [
+        "com.android.runtime",
+        "//apex_available:platform",
+    ],
     defaults: ["debuggerd_defaults"],
     recovery_available: true,
     srcs: [
@@ -118,8 +123,7 @@ cc_library_static {
         "libasync_safe",
         "libbase",
         "libdebuggerd",
-        "libunwindstack",
-        "libdexfile_support_static",  // libunwindstack dependency
+        "libunwindstack_no_dex",
         "liblzma",
         "libcutils",
     ],
@@ -127,14 +131,6 @@ cc_library_static {
     header_libs: ["bionic_libc_platform_headers"],
     export_header_lib_headers: ["bionic_libc_platform_headers"],
 
-    target: {
-        recovery: {
-            exclude_static_libs: [
-                "libdexfile_support_static",
-            ],
-        },
-    },
-
     export_include_dirs: ["include"],
 }
 
@@ -188,7 +184,7 @@ cc_library_static {
     ],
 
     static_libs: [
-        "libdexfile_support_static",  // libunwindstack dependency
+        "libdexfile_support",  // libunwindstack dependency
         "libunwindstack",
         "liblzma",
         "libbase",
@@ -201,7 +197,7 @@ cc_library_static {
     target: {
         recovery: {
             exclude_static_libs: [
-                "libdexfile_support_static",
+                "libdexfile_support",
             ],
         },
     },

init/Android.mk

@@ -105,9 +105,8 @@ LOCAL_STATIC_LIBRARIES := \
     libgsi \
     libcom.android.sysprop.apex \
     liblzma \
-    libdexfile_support_static \
-    libunwindstack \
-    libbacktrace \
+    libunwindstack_no_dex \
+    libbacktrace_no_dex \
     libmodprobe \
     libext2_uuid \
     libprotobuf-cpp-lite \

libbacktrace/Android.bp

@@ -50,20 +50,9 @@ cc_library_headers {
     ],
 }
 
-cc_library {
-    name: "libbacktrace",
-    vendor_available: false,
-    recovery_available: true,
-    apex_available: [
-        "//apex_available:platform",
-        "//apex_available:anyapex",
-    ],
-    vndk: {
-        enabled: true,
-        support_system_process: true,
-    },
+cc_defaults {
+    name: "libbacktrace_defaults",
     defaults: ["libbacktrace_common"],
-    host_supported: true,
 
     cflags: [
         "-Wexit-time-destructors",
@@ -88,7 +77,6 @@ cc_library {
             shared_libs: [
                 "libbase",
                 "liblog",
-                "libunwindstack",
             ],
 
             static_libs: [
@@ -101,6 +89,30 @@ cc_library {
                 whole_static_libs: ["libasync_safe"],
             },
         },
+    },
+}
+
+cc_library {
+    name: "libbacktrace",
+    vendor_available: false,
+    recovery_available: true,
+    apex_available: [
+        "//apex_available:platform",
+        "//apex_available:anyapex",
+    ],
+    vndk: {
+        enabled: true,
+        support_system_process: true,
+    },
+    host_supported: true,
+    defaults: ["libbacktrace_defaults"],
+
+    target: {
+        linux: {
+            shared_libs: [
+                "libunwindstack",
+            ],
+        },
         vendor: {
             cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
         },
@@ -110,6 +122,21 @@ cc_library {
     },
 }
 
+// Static library without DEX support to avoid dependencies on the ART APEX.
+cc_library_static {
+    name: "libbacktrace_no_dex",
+    visibility: ["//system/core/debuggerd"],
+    defaults: ["libbacktrace_defaults"],
+    cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
+    target: {
+        linux: {
+            static_libs: [
+                "libunwindstack_no_dex",
+            ],
+        },
+    },
+}
+
 cc_test_library {
     name: "libbacktrace_test",
     defaults: ["libbacktrace_common"],

libunwindstack/Android.bp

@@ -35,20 +35,13 @@ cc_defaults {
     },
 }
 
-cc_library {
-    name: "libunwindstack",
-    vendor_available: true,
-    recovery_available: true,
-    vndk: {
-        enabled: true,
-        support_system_process: true,
-    },
+cc_defaults {
+    name: "libunwindstack_defaults",
     defaults: ["libunwindstack_flags"],
     export_include_dirs: ["include"],
 
     srcs: [
         "ArmExidx.cpp",
-        "DexFile.cpp",
         "DexFiles.cpp",
         "DwarfCfa.cpp",
         "DwarfEhFrameWithHdr.cpp",
@@ -77,7 +70,6 @@ cc_library {
     ],
 
     cflags: [
-        "-DDEXFILE_SUPPORT",
         "-Wexit-time-destructors",
     ],
 
@@ -89,24 +81,6 @@ cc_library {
                 "-g",
             ],
         },
-        vendor: {
-            cflags: ["-UDEXFILE_SUPPORT"],
-            exclude_srcs: [
-                "DexFile.cpp",
-            ],
-            exclude_shared_libs: [
-                "libdexfile_support",
-            ],
-        },
-        recovery: {
-            cflags: ["-UDEXFILE_SUPPORT"],
-            exclude_srcs: [
-                "DexFile.cpp",
-            ],
-            exclude_shared_libs: [
-                "libdexfile_support",
-            ],
-        },
     },
 
     arch: {
@@ -124,12 +98,56 @@ cc_library {
 
     shared_libs: [
         "libbase",
-        "libdexfile_support",
         "liblog",
         "liblzma",
     ],
 }
 
+cc_library {
+    name: "libunwindstack",
+    vendor_available: true,
+    recovery_available: true,
+    vndk: {
+        enabled: true,
+        support_system_process: true,
+    },
+    defaults: ["libunwindstack_defaults"],
+
+    srcs: ["DexFile.cpp"],
+    cflags: ["-DDEXFILE_SUPPORT"],
+    shared_libs: ["libdexfile_support"],
+
+    target: {
+        vendor: {
+            cflags: ["-UDEXFILE_SUPPORT"],
+            exclude_srcs: ["DexFile.cpp"],
+            exclude_shared_libs: ["libdexfile_support"],
+        },
+        recovery: {
+            cflags: ["-UDEXFILE_SUPPORT"],
+            exclude_srcs: ["DexFile.cpp"],
+            exclude_shared_libs: ["libdexfile_support"],
+        },
+    },
+}
+
+// Static library without DEX support to avoid dependencies on the ART APEX.
+cc_library_static {
+    name: "libunwindstack_no_dex",
+    recovery_available: true,
+    defaults: ["libunwindstack_defaults"],
+
+    visibility: [
+        "//system/core/debuggerd",
+        "//system/core/init",
+        "//system/core/libbacktrace",
+    ],
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.runtime",
+    ],
+}
+
 //-------------------------------------------------------------------------
 // Unit Tests
 //-------------------------------------------------------------------------