Add Android.bp for libc/libm/libdl

Change-Id: I3537363849ba1244348996ff17c5ace1b95dbeee

1 files changed, 47 insertions, 0 deletions

diff --git a/libdl/Android.bp b/libdl/Android.bp
new file mode 100644
index 000000000..46dd0eb7e
--- /dev/null
+++ b/libdl/Android.bp
@@ -0,0 +1,47 @@
+//
+// libdl
+//
+cc_library {
+
+    // NOTE: --exclude-libs=libgcc.a makes sure that any symbols libdl.so pulls from
+    // libgcc.a are made static to libdl.so.  This in turn ensures that libraries that
+    // a) pull symbols from libgcc.a and b) depend on libdl.so will not rely on libdl.so
+    // to provide those symbols, but will instead pull them from libgcc.a.  Specifically,
+    // we use this property to make sure libc.so has its own copy of the code from
+    // libgcc.a it uses.
+    //
+    // DO NOT REMOVE --exclude-libs!
+
+    ldflags: ["-Wl,--exclude-libs=libgcc.a"],
+    version_script: "libdl.map",
+
+    // for x86, exclude libgcc_eh.a for the same reasons as above
+    arch: {
+        x86: {
+            ldflags: ["-Wl,--exclude-libs=libgcc_eh.a"],
+        },
+        x86_64: {
+            ldflags: ["-Wl,--exclude-libs=libgcc_eh.a"],
+        },
+    },
+    srcs: ["libdl.c"],
+    cflags: [
+        "-Wall",
+        "-Wextra",
+        "-Wunused",
+        "-Werror",
+    ],
+    stl: "none",
+
+    name: "libdl",
+
+    // NOTE: libdl needs __aeabi_unwind_cpp_pr0 from libgcc.a but libgcc.a needs a
+    // few symbols from libc. Using --no-undefined here results in having to link
+    // against libc creating a circular dependency which is removed and we end up
+    // with missing symbols. Since this library is just a bunch of stubs, we set
+    // LOCAL_ALLOW_UNDEFINED_SYMBOLS to remove --no-undefined from the linker flags.
+    allow_undefined_symbols: true,
+    system_shared_libs: [],
+
+    sanitize: ["never"],
+}