commit 45dbffdc3d918e0d23638c41049cf1997c93b0d1
author Kuba Brecka <kuba.brecka@gmail.com> Thu Jul 23 10:54:06 2015 +0000
committer Kuba Brecka <kuba.brecka@gmail.com> Thu Jul 23 10:54:06 2015 +0000
tree 09e8a408c6ac07c1b7e5fe626adb5ffe8817ad05
parent cdc1246750163de49a4357444f47aaef9ffc6323

[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

llvm-svn: 243003

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index c7f3cfb..5dde5fe 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -91,7 +91,9 @@
     "__asan_unregister_globals";
 static const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
 static const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
-static const char *const kAsanInitName = "__asan_init_v5";
+static const char *const kAsanInitName = "__asan_init";
+static const char *const kAsanVersionCheckName =
+    "__asan_version_mismatch_check_v6";
 static const char *const kAsanPtrCmp = "__sanitizer_ptr_cmp";
 static const char *const kAsanPtrSub = "__sanitizer_ptr_sub";
 static const char *const kAsanHandleNoReturnName = "__asan_handle_no_return";
@@ -1468,9 +1470,9 @@
 
   if (!CompileKernel) {
     std::tie(AsanCtorFunction, AsanInitFunction) =
-        createSanitizerCtorAndInitFunctions(M, kAsanModuleCtorName, kAsanInitName,
-                                            /*InitArgTypes=*/{},
-                                            /*InitArgs=*/{});
+        createSanitizerCtorAndInitFunctions(
+            M, kAsanModuleCtorName, kAsanInitName,
+            /*InitArgTypes=*/{}, /*InitArgs=*/{}, kAsanVersionCheckName);
     appendToGlobalCtors(M, AsanCtorFunction, kAsanCtorAndDtorPriority);
   }
   Mapping = getShadowMapping(TargetTriple, LongSize, CompileKernel);

llvm/lib/Transforms/Utils/ModuleUtils.cpp

diff --git a/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
index d69a81e..c5abf76 100644
--- a/llvm/lib/Transforms/Utils/ModuleUtils.cpp
+++ b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
@@ -107,7 +107,8 @@
 
 std::pair<Function *, Function *> llvm::createSanitizerCtorAndInitFunctions(
     Module &M, StringRef CtorName, StringRef InitName,
-    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs) {
+    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs,
+    StringRef VersionCheckName) {
   assert(!InitName.empty() && "Expected init function name");
   assert(InitArgTypes.size() == InitArgTypes.size() &&
          "Sanitizer's init function expects different number of arguments");
@@ -122,6 +123,13 @@
           AttributeSet()));
   InitFunction->setLinkage(Function::ExternalLinkage);
   IRB.CreateCall(InitFunction, InitArgs);
+  if (!VersionCheckName.empty()) {
+    Function *VersionCheckFunction =
+        checkSanitizerInterfaceFunction(M.getOrInsertFunction(
+            VersionCheckName, FunctionType::get(IRB.getVoidTy(), {}, false),
+            AttributeSet()));
+    IRB.CreateCall(VersionCheckFunction, {});
+  }
   return std::make_pair(Ctor, InitFunction);
 }