Add cmake build support for lsan on OS X

Summary:
Adds a new cmake flag 'COMPILER_RT_ENABLE_LSAN_OSX', which enables lsan
compilation and is turned off by default. Patches to fix build errors
when this flag is enabled will be uploaded soon.

This is part of an effort to port LSan to OS X, but LSan on OS X does not
currently work or pass tests currently.

Reviewers: kubamracek, kcc, glider, alekseyshl

Reviewed By: kubamracek

Subscribers: danalbert, srhines, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D29783

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@295012 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 35 insertions, 10 deletions

diff --git a/lib/lsan/CMakeLists.txt b/lib/lsan/CMakeLists.txt
index e78bf6d3e..a48b85fa6 100644
--- a/lib/lsan/CMakeLists.txt
+++ b/lib/lsan/CMakeLists.txt
@@ -17,6 +17,10 @@ set(LSAN_SOURCES
 
 set(LSAN_SRC_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 
+# FIXME(fjricci) - remove this once lsan for darwin is fully enabled
+if(APPLE AND COMPILER_RT_HAS_LSAN)
+  set(LSAN_CFLAGS ${LSAN_CFLAGS} -DCAN_SANITIZE_LEAKS_MAC=1)
+endif()
 add_compiler_rt_object_libraries(RTLSanCommon
     OS ${SANITIZER_COMMON_SUPPORTED_OS}
     ARCHS ${LSAN_COMMON_SUPPORTED_ARCH}
@@ -25,16 +29,34 @@ add_compiler_rt_object_libraries(RTLSanCommon
 
 if(COMPILER_RT_HAS_LSAN)
   add_compiler_rt_component(lsan)
-  foreach(arch ${LSAN_SUPPORTED_ARCH})
+  if(APPLE)
+    add_weak_symbols("lsan" WEAK_SYMBOL_LINK_FLAGS)
+    add_weak_symbols("sanitizer_common" WEAK_SYMBOL_LINK_FLAGS)
+
     add_compiler_rt_runtime(clang_rt.lsan
-      STATIC
-      ARCHS ${arch}
+      SHARED
+      OS ${SANITIZER_COMMON_SUPPORTED_OS}
+      ARCHS ${LSAN_SUPPORTED_ARCH}
       SOURCES ${LSAN_SOURCES}
-              $<TARGET_OBJECTS:RTInterception.${arch}>
-              $<TARGET_OBJECTS:RTSanitizerCommon.${arch}>
-              $<TARGET_OBJECTS:RTSanitizerCommonLibc.${arch}>
-              $<TARGET_OBJECTS:RTLSanCommon.${arch}>
+      OBJECT_LIBS RTLSanCommon
+                  RTInterception
+                  RTSanitizerCommon
+                  RTSanitizerCommonLibc
       CFLAGS ${LSAN_CFLAGS}
+      LINK_FLAGS ${WEAK_SYMBOL_LINK_FLAGS}
       PARENT_TARGET lsan)
-  endforeach()
+  else()
+    foreach(arch ${LSAN_SUPPORTED_ARCH})
+      add_compiler_rt_runtime(clang_rt.lsan
+        STATIC
+        ARCHS ${arch}
+        SOURCES ${LSAN_SOURCES}
+                $<TARGET_OBJECTS:RTInterception.${arch}>
+                $<TARGET_OBJECTS:RTSanitizerCommon.${arch}>
+                $<TARGET_OBJECTS:RTSanitizerCommonLibc.${arch}>
+                $<TARGET_OBJECTS:RTLSanCommon.${arch}>
+        CFLAGS ${LSAN_CFLAGS}
+        PARENT_TARGET lsan)
+    endforeach()
+  endif()
 endif()
diff --git a/lib/lsan/lsan_common.h b/lib/lsan/lsan_common.h
index 67d43a2a3..f1ec64785 100644
--- a/lib/lsan/lsan_common.h
+++ b/lib/lsan/lsan_common.h
@@ -30,8 +30,9 @@
 // To enable LeakSanitizer on new architecture, one need to implement
 // internal_clone function as well as (probably) adjust TLS machinery for
 // new architecture inside sanitizer library.
-#if (SANITIZER_LINUX && !SANITIZER_ANDROID) && (SANITIZER_WORDSIZE == 64) \
-     && (defined(__x86_64__) ||  defined(__mips64) ||  defined(__aarch64__))
+#if (SANITIZER_LINUX && !SANITIZER_ANDROID || CAN_SANITIZE_LEAKS_MAC) \
+     && (SANITIZER_WORDSIZE == 64) && (defined(__x86_64__) \
+     ||  defined(__mips64) ||  defined(__aarch64__))
 #define CAN_SANITIZE_LEAKS 1
 #elif SANITIZER_LINUX && !SANITIZER_ANDROID && defined(__i386__)
 #define CAN_SANITIZE_LEAKS 1
diff --git a/lib/lsan/weak_symbols.txt b/lib/lsan/weak_symbols.txt
new file mode 100644
index 000000000..da4f994da
--- /dev/null
+++ b/lib/lsan/weak_symbols.txt
@@ -0,0 +1,2 @@
+___lsan_default_suppressions
+___lsan_is_turned_off