Stop exporting symbols from app_process
Any symbols exported from the executable override everything else in
every linker namespace. Previously, app_process exported the
signal/sigchain API, but that interposition is now handled by
libsigchain.so.
Bug: http://b/190100879
Test: `nm -D --defined-only app_process{32,64}` shows no symbols
Change-Id: I1ab1fc700c34e91535c3e679a471debbb4eb71e3
diff --git a/cmds/app_process/Android.bp b/cmds/app_process/Android.bp
index 0eff83c..a157517 100644
--- a/cmds/app_process/Android.bp
+++ b/cmds/app_process/Android.bp
@@ -29,7 +29,16 @@
},
},
- ldflags: ["-Wl,--export-dynamic"],
+ // Symbols exported from the executable in .dynsym interpose symbols in every
+ // linker namespace, including an app's classloader namespace. Provide this
+ // version script to prevent unwanted interposition.
+ //
+ // By default, the static linker doesn't export most of an executable's symbols,
+ // but it will export a symbol that appears to override a symbol in a needed DSO.
+ // This commonly happens with C++ vaguely-linked entities, such as template
+ // functions or type_info variables. Hence, a version script is needed even for
+ // an executable.
+ version_script: "version-script.txt",
shared_libs: [
"libandroid_runtime",
diff --git a/cmds/app_process/version-script.txt b/cmds/app_process/version-script.txt
new file mode 100644
index 0000000..a98066a
--- /dev/null
+++ b/cmds/app_process/version-script.txt
@@ -0,0 +1,4 @@
+{
+ local:
+ *;
+};
