[compiler-rt] r243004 - [asan] Rename the ABI versioning symbol to '__asan_version_mismatch_check' instead of abusing '__asan_init'

[Kuba Brecka]

Author: kuba.brecka
Date: Thu Jul 23 05:55:13 2015
New Revision: 243004

URL: http://llvm.org/viewvc/llvm-project?rev=243004&view=rev
Log:
[asan] Rename the ABI versioning symbol to '__asan_version_mismatch_check' instead of abusing '__asan_init'

We currently version `__asan_init` and when the ABI version doesn't match, the linker gives a `undefined reference to '__asan_init_v5'` message. From this, it might not be obvious that it's actually a version mismatch error. This patch makes the error message much clearer by changing the name of the undefined symbol to be `__asan_version_mismatch_check_xxx` (followed by the version string). We obviously don't want the initializer to be named like that, so it's a separate symbol that is used only for the purpose of version checking.

Reviewed at http://reviews.llvm.org/D11004


Modified:
    compiler-rt/trunk/lib/asan/asan_init_version.h
    compiler-rt/trunk/lib/asan/asan_interface_internal.h
    compiler-rt/trunk/lib/asan/asan_rtl.cc
    compiler-rt/trunk/lib/asan/asan_win_dll_thunk.cc
    compiler-rt/trunk/test/asan/TestCases/Darwin/interface_symbols_darwin.c
    compiler-rt/trunk/test/asan/TestCases/Linux/interface_symbols_linux.c

Modified: compiler-rt/trunk/lib/asan/asan_init_version.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_init_version.h?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_init_version.h (original)
+++ compiler-rt/trunk/lib/asan/asan_init_version.h Thu Jul 23 05:55:13 2015
@@ -27,8 +27,8 @@ extern "C" {
   // v3=>v4: added '__asan_global_source_location' to __asan_global.
   // v4=>v5: changed the semantics and format of __asan_stack_malloc_ and
   //         __asan_stack_free_ functions.
-  #define __asan_init __asan_init_v5
-  #define __asan_init_name "__asan_init_v5"
+  // v5=>v6: changed the name of the version check symbol
+  #define __asan_version_mismatch_check __asan_version_mismatch_check_v6
 }
 
 #endif  // ASAN_INIT_VERSION_H

Modified: compiler-rt/trunk/lib/asan/asan_interface_internal.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_interface_internal.h?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_interface_internal.h (original)
+++ compiler-rt/trunk/lib/asan/asan_interface_internal.h Thu Jul 23 05:55:13 2015
@@ -27,10 +27,14 @@ using __sanitizer::uptr;
 extern "C" {
   // This function should be called at the very beginning of the process,
   // before any instrumented code is executed and before any call to malloc.
-  // Please note that __asan_init is a macro that is replaced with
-  // __asan_init_vXXX at compile-time.
   SANITIZER_INTERFACE_ATTRIBUTE void __asan_init();
 
+  // This function exists purely to get a linker/loader error when using
+  // incompatible versions of instrumentation and runtime library. Please note
+  // that __asan_version_mismatch_check is a macro that is replaced with
+  // __asan_version_mismatch_check_vXXX at compile-time.
+  SANITIZER_INTERFACE_ATTRIBUTE void __asan_version_mismatch_check();
+
   // This structure is used to describe the source location of a place where
   // global was defined.
   struct __asan_global_source_location {

Modified: compiler-rt/trunk/lib/asan/asan_rtl.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_rtl.cc?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_rtl.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_rtl.cc Thu Jul 23 05:55:13 2015
@@ -586,3 +586,7 @@ void __asan_init() {
   AsanActivate();
   AsanInitInternal();
 }
+
+void __asan_version_mismatch_check() {
+  // Do nothing.
+}

Modified: compiler-rt/trunk/lib/asan/asan_win_dll_thunk.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_win_dll_thunk.cc?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_win_dll_thunk.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_win_dll_thunk.cc Thu Jul 23 05:55:13 2015
@@ -210,7 +210,7 @@ extern "C" {
     // __asan_init is expected to be called by only one thread.
     if (fn) return;
 
-    fn = (fntype)getRealProcAddressOrDie(__asan_init_name);
+    fn = (fntype)getRealProcAddressOrDie("__asan_init");
     fn();
     __asan_option_detect_stack_use_after_return =
         (__asan_should_detect_stack_use_after_return() != 0);

Modified: compiler-rt/trunk/test/asan/TestCases/Darwin/interface_symbols_darwin.c
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/Darwin/interface_symbols_darwin.c?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/Darwin/interface_symbols_darwin.c (original)
+++ compiler-rt/trunk/test/asan/TestCases/Darwin/interface_symbols_darwin.c Thu Jul 23 05:55:13 2015
@@ -8,7 +8,7 @@
 // RUN: nm -g `%clang_asan %s -fsanitize=address -### 2>&1 | grep "libclang_rt.asan_osx_dynamic.dylib" | sed -e 's/.*"\(.*libclang_rt.asan_osx_dynamic.dylib\)".*/\1/'` \
 // RUN:   | grep " T " | sed "s/.* T //" \
 // RUN:   | grep "__asan_" | sed "s/___asan_/__asan_/" \
-// RUN:   | sed -E "s/__asan_init_v[0-9]+/__asan_init/" \
+// RUN:   | sed -E "s/__asan_version_mismatch_check_v[0-9]+/__asan_version_mismatch_check/" \
 // RUN:   | grep -v "__asan_default_options" \
 // RUN:   | grep -v "__asan_on_error" > %t.symbols
 

Modified: compiler-rt/trunk/test/asan/TestCases/Linux/interface_symbols_linux.c
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/Linux/interface_symbols_linux.c?rev=243004&r1=243003&r2=243004&view=diff
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/Linux/interface_symbols_linux.c (original)
+++ compiler-rt/trunk/test/asan/TestCases/Linux/interface_symbols_linux.c Thu Jul 23 05:55:13 2015
@@ -3,7 +3,7 @@
 // RUN: %clang_asan -O2 %s -o %t.exe
 // RUN: nm -D %t.exe | grep " T " | sed "s/.* T //" \
 // RUN:    | grep "__asan_" | sed "s/___asan_/__asan_/" \
-// RUN:    | sed -E "s/__asan_init_v[0-9]+/__asan_init/" \
+// RUN:    | sed -E "s/__asan_version_mismatch_check_v[0-9]+/__asan_version_mismatch_check/" \
 // RUN:    | grep -v "__asan_default_options" \
 // RUN:    | grep -v "__asan_stack_" \
 // RUN:    | grep -v "__asan_on_error" > %t.symbols