r310733 - Add -fsanitize=fuzzer-no-link flag to the driver.

[George Karpenkov via cfe-commits]

Author: george.karpenkov
Date: Fri Aug 11 10:22:58 2017
New Revision: 310733

URL: http://llvm.org/viewvc/llvm-project?rev=310733&view=rev
Log:
Add -fsanitize=fuzzer-no-link flag to the driver.

The flag will perform instrumentation necessary to the fuzzing,
but will NOT link libLLVMFuzzer.a library.
Necessary when modifying CFLAGS for projects which may produce
executables as well as a fuzzable target.

Differential Revision: https://reviews.llvm.org/D36600

Modified:
    cfe/trunk/include/clang/Basic/Sanitizers.def
    cfe/trunk/lib/Driver/SanitizerArgs.cpp
    cfe/trunk/lib/Driver/ToolChains/Darwin.cpp
    cfe/trunk/lib/Driver/ToolChains/Linux.cpp
    cfe/trunk/test/Driver/fuzzer.c

Modified: cfe/trunk/include/clang/Basic/Sanitizers.def
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Sanitizers.def?rev=310733&r1=310732&r2=310733&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/Sanitizers.def (original)
+++ cfe/trunk/include/clang/Basic/Sanitizers.def Fri Aug 11 10:22:58 2017
@@ -50,6 +50,9 @@ SANITIZER("memory", Memory)
 // libFuzzer
 SANITIZER("fuzzer", Fuzzer)
 
+// libFuzzer-required instrumentation, no linking.
+SANITIZER("fuzzer-no-link", FuzzerNoLink)
+
 // ThreadSanitizer
 SANITIZER("thread", Thread)
 

Modified: cfe/trunk/lib/Driver/SanitizerArgs.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/SanitizerArgs.cpp?rev=310733&r1=310732&r2=310733&view=diff
==============================================================================
--- cfe/trunk/lib/Driver/SanitizerArgs.cpp (original)
+++ cfe/trunk/lib/Driver/SanitizerArgs.cpp Fri Aug 11 10:22:58 2017
@@ -32,7 +32,7 @@ enum : SanitizerMask {
   RequiresPIE = DataFlow,
   NeedsUnwindTables = Address | Thread | Memory | DataFlow,
   SupportsCoverage = Address | KernelAddress | Memory | Leak | Undefined |
-                     Integer | Nullability | DataFlow | Fuzzer,
+                     Integer | Nullability | DataFlow | Fuzzer | FuzzerNoLink,
   RecoverableByDefault = Undefined | Integer | Nullability,
   Unrecoverable = Unreachable | Return,
   LegacyFsanitizeRecoverMask = Undefined | Integer,
@@ -286,8 +286,11 @@ SanitizerArgs::SanitizerArgs(const ToolC
       Add &= ~InvalidTrappingKinds;
       Add &= Supported;
 
-      // Enable coverage if the fuzzing flag is set.
       if (Add & Fuzzer)
+        Add |= FuzzerNoLink;
+
+      // Enable coverage if the fuzzing flag is set.
+      if (Add & FuzzerNoLink)
         CoverageFeatures |= CoverageTracePCGuard | CoverageIndirCall |
                             CoverageTraceCmp | CoveragePCTable;
 

Modified: cfe/trunk/lib/Driver/ToolChains/Darwin.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains/Darwin.cpp?rev=310733&r1=310732&r2=310733&view=diff
==============================================================================
--- cfe/trunk/lib/Driver/ToolChains/Darwin.cpp (original)
+++ cfe/trunk/lib/Driver/ToolChains/Darwin.cpp Fri Aug 11 10:22:58 2017
@@ -2018,6 +2018,7 @@ SanitizerMask Darwin::getSupportedSaniti
   Res |= SanitizerKind::Address;
   Res |= SanitizerKind::Leak;
   Res |= SanitizerKind::Fuzzer;
+  Res |= SanitizerKind::FuzzerNoLink;
   if (isTargetMacOS()) {
     if (!isMacosxVersionLT(10, 9))
       Res |= SanitizerKind::Vptr;

Modified: cfe/trunk/lib/Driver/ToolChains/Linux.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains/Linux.cpp?rev=310733&r1=310732&r2=310733&view=diff
==============================================================================
--- cfe/trunk/lib/Driver/ToolChains/Linux.cpp (original)
+++ cfe/trunk/lib/Driver/ToolChains/Linux.cpp Fri Aug 11 10:22:58 2017
@@ -828,6 +828,7 @@ SanitizerMask Linux::getSupportedSanitiz
   SanitizerMask Res = ToolChain::getSupportedSanitizers();
   Res |= SanitizerKind::Address;
   Res |= SanitizerKind::Fuzzer;
+  Res |= SanitizerKind::FuzzerNoLink;
   Res |= SanitizerKind::KernelAddress;
   Res |= SanitizerKind::Vptr;
   Res |= SanitizerKind::SafeStack;

Modified: cfe/trunk/test/Driver/fuzzer.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Driver/fuzzer.c?rev=310733&r1=310732&r2=310733&view=diff
==============================================================================
--- cfe/trunk/test/Driver/fuzzer.c (original)
+++ cfe/trunk/test/Driver/fuzzer.c Fri Aug 11 10:22:58 2017
@@ -21,6 +21,11 @@
 // RUN: %clang -fsanitize=fuzzer %s -shared -o %t.so -### 2>&1 | FileCheck --check-prefixes=CHECK-NOLIB-SO %s
 // CHECK-NOLIB-SO-NOT: libLLVMFuzzer.a
 
+// Check that we don't link in libFuzzer when compiling with -fsanitize=fuzzer-no-link.
+// RUN: %clang -fsanitize=fuzzer-no-link %s -target x86_64-apple-darwin14 -### 2>&1 | FileCheck --check-prefixes=CHECK-NOLIB,CHECK-COV %s
+// CHECK-NOLIB-NOT: libLLVMFuzzer.a
+// CHECK-COV: -fsanitize-coverage-trace-pc-guard
+
 // RUN: %clang -fsanitize=fuzzer -fsanitize-coverage=trace-pc %s -### 2>&1 | FileCheck --check-prefixes=CHECK-MSG %s
 // CHECK-MSG-NOT: argument unused during compilation