[compiler-rt] r238367 - [asan] Fix build dependency issues with ASan version list file.

[Evgeniy Stepanov]

Author: eugenis
Date: Wed May 27 17:38:01 2015
New Revision: 238367

URL: http://llvm.org/viewvc/llvm-project?rev=238367&view=rev
Log:
[asan] Fix build dependency issues with ASan version list file.

CMake pre-3.1 has a bug where a shared library depending on a custom_target
does not really depend on it.

This commit implements a hilariously ugly workaround for this problem, see
code comments for more details.

Modified:
    compiler-rt/trunk/lib/asan/CMakeLists.txt

Modified: compiler-rt/trunk/lib/asan/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/CMakeLists.txt?rev=238367&r1=238366&r2=238367&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/CMakeLists.txt (original)
+++ compiler-rt/trunk/lib/asan/CMakeLists.txt Wed May 27 17:38:01 2015
@@ -96,6 +96,12 @@ else()
       SOURCES ${ASAN_SOURCES} ${ASAN_CXX_SOURCES}
       CFLAGS ${ASAN_DYNAMIC_CFLAGS}
       DEFS ${ASAN_DYNAMIC_DEFINITIONS})
+
+    file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/dummy.cc "")
+    add_compiler_rt_object_library(RTAsan_dynamic_version_script_dummy ${arch}
+      SOURCES ${CMAKE_CURRENT_BINARY_DIR}/dummy.cc
+      CFLAGS ${ASAN_DYNAMIC_CFLAGS}
+      DEFS ${ASAN_DYNAMIC_DEFINITIONS})
   endforeach()
 endif()
 
@@ -149,9 +155,12 @@ else()
       add_sanitizer_rt_version_list(clang_rt.asan-dynamic-${arch}
                                     LIB clang_rt.asan-${arch} clang_rt.asan_cxx-${arch}
                                     EXTRA asan.syms.extra)
-      add_dependencies(asan clang_rt.asan-dynamic-${arch}-version-list)
       set(VERSION_SCRIPT_FLAG
            -Wl,--version-script,${CMAKE_CURRENT_BINARY_DIR}/clang_rt.asan-dynamic-${arch}.vers)
+      set_source_files_properties(
+        ${CMAKE_CURRENT_BINARY_DIR}/dummy.cc
+	PROPERTIES
+	OBJECT_DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/clang_rt.asan-dynamic-${arch}.vers)
     else()
       set(VERSION_SCRIPT_FLAG)
     endif()
@@ -164,6 +173,11 @@ else()
     add_compiler_rt_runtime(clang_rt.asan-dynamic-${arch} ${arch} SHARED
       OUTPUT_NAME ${SHARED_ASAN_NAME}
       SOURCES $<TARGET_OBJECTS:RTAsan_dynamic.${arch}>
+              # The only purpose of RTAsan_dynamic_version_script_dummy is to carry
+              # a dependency of the shared runtime on the version script. With CMake
+              # 3.1 or later it can be replaced with a straightforward
+              # add_dependencies(clang_rt.asan-dynamic-${arch} clang_rt.asan-dynamic-${arch}-version-list)
+              $<TARGET_OBJECTS:RTAsan_dynamic_version_script_dummy.${arch}>
               $<TARGET_OBJECTS:RTUbsan_cxx.${arch}>
               ${ASAN_COMMON_RUNTIME_OBJECTS}
       CFLAGS ${ASAN_DYNAMIC_CFLAGS}
@@ -174,7 +188,6 @@ else()
     add_dependencies(asan clang_rt.asan-dynamic-${arch})
 
     if (UNIX AND NOT ${arch} MATCHES "i386|i686")
-      add_dependencies(clang_rt.asan-dynamic-${arch} clang_rt.asan-dynamic-${arch}-version-list)
       add_sanitizer_rt_symbols(clang_rt.asan_cxx-${arch})
       add_dependencies(asan clang_rt.asan_cxx-${arch}-symbols)
       add_sanitizer_rt_symbols(clang_rt.asan-${arch} asan.syms.extra)