Add workaround #988 the default wrap.sh.

This can't help users of the static STL, but it does help those using
the shared STL.

Also clean up by merging these into a single wrap.sh. There should
never be more than one ASan library in the directory, so we can just
use a wildcard.

Test: https://github.com/DanAlbert/asan-wrap-sh-exceptions-crash-repro
Bug: android/ndk#988
Change-Id: I890ba18faaebcdafe61f2800cc062ec7b5d9502e

build/core/sanitizers.mk

@@ -44,7 +44,6 @@ include $(BUILD_SYSTEM)/install_sanitizer.mk
 # default ASAN wrap.sh for them.
 ifneq (,$(filter address,$(NDK_SANITIZERS)))
     ifeq ($(NDK_NO_USER_WRAP_SH),true)
-        NDK_APP_WRAP_SH_$(TARGET_ARCH_ABI) := \
-            $(NDK_ROOT)/wrap.sh/asan.$(TARGET_ARCH_ABI).sh
+        NDK_APP_WRAP_SH_$(TARGET_ARCH_ABI) := $(NDK_ROOT)/wrap.sh/asan.sh
     endif
 endif

docs/BuildSystemMaintainers.md

@@ -325,9 +325,9 @@ than Valgrind (roughly 50% performance compared to an unsanitized application).
 To use ASan, pass `-fsanitize=address` when both compiling and linking. The
 sanitizer runtime libraries are installed to
 `<NDK>/toolchains/llvm/prebuilt/<host-tag>/lib64/clang/<clang-version>/lib/linux`.
-The library is named `libclang_rt.asan-<arch>-android.so`.  This library must be
-included in the APK. A [wrap.sh] file must also be included in the APK. Premade
-wrap.sh files for ASan are installed to `<NDK>/wrap.sh`.
+The library is named `libclang_rt.asan-<arch>-android.so`. This library must be
+included in the APK. A [wrap.sh] file must also be included in the APK. A
+premade wrap.sh file for ASan is installed to `<NDK>/wrap.sh`.
 
 Note: wrap.sh is only available for [debuggable] APKs running on Android Oreo
 (API 26) or higher. ASan can still be used devices prior to Oreo but at least

wrap.sh/asan.sh

@@ -0,0 +1,11 @@
+#!/system/bin/sh
+HERE="$(cd "$(dirname "$0")" && pwd)"
+export ASAN_OPTIONS=log_to_syslog=false,allow_user_segv_handler=1
+ASAN_LIB=$(ls $HERE/libclang_rt.asan-*-android.so)
+if [ -f "$HERE/libc++_shared.so" ]; then
+    # Workaround for https://github.com/android-ndk/ndk/issues/988.
+    export LD_PRELOAD="$ASAN_LIB $HERE/libc++_shared.so"
+else
+    export LD_PRELOAD="$ASAN_LIB"
+fi
+"$@"