[Driver] Make -fsanitize=kcfi,function incompatible

A -fsanitize=kcfi instrumented function has a special instruction/data
before the function entry at a fixed offset.
A -fsanitize=function instrumented function has special instruction/data
after the function entry at a fixed offset (may change to *before* in D148665).

The two instrumentations are not intended to be used together and will become
incompatible after D148665.

Reviewed By: samitolvanen

Differential Revision: https://reviews.llvm.org/D148671

diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index d0dd294..8fe8ef2 100644 (file)
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -517,7 +517,8 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
       std::make_pair(SanitizerKind::MemTag,
                      SanitizerKind::Address | SanitizerKind::KernelAddress |
                          SanitizerKind::HWAddress |
-                         SanitizerKind::KernelHWAddress)};
+                         SanitizerKind::KernelHWAddress),
+      std::make_pair(SanitizerKind::KCFI, SanitizerKind::Function)};
   // Enable toolchain specific default sanitizers if not explicitly disabled.
   SanitizerMask Default = TC.getDefaultSanitizers() & ~AllRemove;
 

diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
index 3b89e13..e12f11b 100644 (file)
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -674,6 +674,9 @@
 // RUN: %clang --target=x86_64-linux-gnu -fsanitize=kcfi -fno-sanitize-recover=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-KCFI-RECOVER
 // CHECK-KCFI-RECOVER: error: unsupported argument 'kcfi' to option '-fno-sanitize-recover='
 
+// RUN: %clang --target=x86_64-linux-gnu -fsanitize=kcfi,function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-KCFI-FUNCTION
+// CHECK-KCFI-FUNCTION: error: invalid argument '-fsanitize=kcfi' not allowed with '-fsanitize=function'
+
 // RUN: %clang_cl -fsanitize=address -c -MDd -### -- %s 2>&1 | FileCheck %s -check-prefix=CHECK-ASAN-DEBUGRTL
 // RUN: %clang_cl -fsanitize=address -c -MTd -### -- %s 2>&1 | FileCheck %s -check-prefix=CHECK-ASAN-DEBUGRTL
 // RUN: %clang_cl -fsanitize=address -c -LDd -### -- %s 2>&1 | FileCheck %s -check-prefix=CHECK-ASAN-DEBUGRTL