Cleanup and generalize -shared-libasan.

[eugenis]

Summary

• Add -static-libasan for targets that default to shared.
• Remove an Android special case. It is now possible (but untested) to use static compiler-rt libraries there.
• Support libclang_rt.ubsan_standalone as a shared library.

Unlike GCC, this change applies -shared-libasan / -static-libasan to all sanitizers.
I don't see a point in multiple flags like -shared-libubsan, considering that most sanitizers
are not compatible with each other, and each link has basically a single shared/static choice.

[rsmith]

Could we perhaps rename these flags to e.g. -static-libsan (with a -static-libasan alias for compatibility)? It seems confusing that the way to enable a static tsan runtime would be with -static-libasan.

[vitalybuka]

In D38525#888826, @rsmith wrote:

Could we perhaps rename these flags to e.g. -static-libsan (with a -static-libasan alias for compatibility)? It seems confusing that the way to enable a static tsan runtime would be with -static-libasan.

I like this idea as well. If we go this way we need to deprecate "shared-libasan" and avoid adding "static-libasan.

[eugenis]

renamed flags to *-libsan

[vitalybuka]

clang/lib/Driver/SanitizerArgs.cpp

614

SharedRuntime = Args.hasFlag(options::OPT_shared_libsan,,
                     options::OPT_static_libsan,
                     TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia());

clang/lib/Driver/ToolChains/CommonArgs.cpp

563

Shouldn't ubsan changes be in the separate patch?

[eugenis]

clang/lib/Driver/ToolChains/CommonArgs.cpp

563

They are quite hard to separate, and without ubsan there is not much point to this change.

[eugenis]

address comment

[eugenis]

clang/lib/Driver/SanitizerArgs.cpp

614

good!

clang/include/clang/Driver/Options.td

 def fPIE : Flag<["-"], "fPIE">, Group<f_Group>;
 def fno_PIE : Flag<["-"], "fno-PIE">, Group<f_Group>;
 def faccess_control : Flag<["-"], "faccess-control">, Group<f_Group>;
 def fallow_unsupported : Flag<["-"], "fallow-unsupported">, Group<f_Group>;
 def fapple_kext : Flag<["-"], "fapple-kext">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Use Apple's kernel extensions ABI">;
 def fapple_pragma_pack : Flag<["-"], "fapple-pragma-pack">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Enable Apple gcc-compatible #pragma pack handling">;
-def shared_libasan : Flag<["-"], "shared-libasan">;
+def shared_libsan : Flag<["-"], "shared-libsan">;
+def static_libsan : Flag<["-"], "static-libsan">;
+def : Flag<["-"], "shared-libasan">, Alias<shared_libsan>;
 def fasm : Flag<["-"], "fasm">, Group<f_Group>;
 
 def fasm_blocks : Flag<["-"], "fasm-blocks">, Group<f_Group>, Flags<[CC1Option]>;
 def fno_asm_blocks : Flag<["-"], "fno-asm-blocks">, Group<f_Group>;
 
 def fassume_sane_operator_new : Flag<["-"], "fassume-sane-operator-new">, Group<f_Group>;
 def fastcp : Flag<["-"], "fastcp">, Group<f_Group>;
 def fastf : Flag<["-"], "fastf">, Group<f_Group>;

clang/include/clang/Driver/SanitizerArgs.h

class SanitizerArgs {
 
   std::vector<std::string> BlacklistFiles;
   std::vector<std::string> ExtraDeps;
   int CoverageFeatures = 0;
   int MsanTrackOrigins = 0;
   bool MsanUseAfterDtor = false;
   bool CfiCrossDso = false;
   int AsanFieldPadding = 0;
-  bool AsanSharedRuntime = false;
+  bool SharedRuntime = false;
   bool AsanUseAfterScope = true;
   bool AsanGlobalsDeadStripping = false;
   bool LinkCXXRuntimes = false;
   bool NeedPIE = false;
   bool SafeStackRuntime = false;
   bool Stats = false;
   bool TsanMemoryAccess = true;
   bool TsanFuncEntryExit = true;
   bool TsanAtomics = true;
   bool MinimalRuntime = false;
 
  public:
   /// Parses the sanitizer arguments from an argument list.
   SanitizerArgs(const ToolChain &TC, const llvm::opt::ArgList &Args);
 
+  bool needsSharedRt() const { return SharedRuntime; }
+
   bool needsAsanRt() const { return Sanitizers.has(SanitizerKind::Address); }
-  bool needsSharedAsanRt() const { return AsanSharedRuntime; }
   bool needsTsanRt() const { return Sanitizers.has(SanitizerKind::Thread); }
   bool needsMsanRt() const { return Sanitizers.has(SanitizerKind::Memory); }
   bool needsFuzzer() const { return Sanitizers.has(SanitizerKind::Fuzzer); }
   bool needsLsanRt() const {
     return Sanitizers.has(SanitizerKind::Leak) &&
            !Sanitizers.has(SanitizerKind::Address);
   }
   bool needsUbsanRt() const;

clang/lib/Driver/SanitizerArgs.cpp

if (!(CoverageFeatures & InsertionPointTypes)) {
     if (CoverageFeatures &
         (CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters))
       CoverageFeatures |= CoverageEdge;
 
     if (CoverageFeatures & CoverageStackDepth)
       CoverageFeatures |= CoverageFunc;
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_shared_libsan,
+                               options::OPT_static_libsan))
+    SharedRuntime = A->getOption().matches(options::OPT_shared_libsan);
+  else
+    SharedRuntime = TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia();
+
   if (AllAddedKinds & Address) {
-    AsanSharedRuntime =
-        Args.hasArg(options::OPT_shared_libasan) ||
-        TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia();
     NeedPIE |= TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia();
     if (Arg *A =
             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
         StringRef S = A->getValue();
         // Legal values are 0 and 1, 2, but in future we may add more levels.
         if (S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
             AsanFieldPadding > 2) {
           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;

clang/lib/Driver/ToolChains/CommonArgs.cpp

 collectSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
                          SmallVectorImpl<StringRef> &SharedRuntimes,
                          SmallVectorImpl<StringRef> &StaticRuntimes,
                          SmallVectorImpl<StringRef> &NonWholeStaticRuntimes,
                          SmallVectorImpl<StringRef> &HelperStaticRuntimes,
                          SmallVectorImpl<StringRef> &RequiredSymbols) {
   const SanitizerArgs &SanArgs = TC.getSanitizerArgs();
   // Collect shared runtimes.
-  if (SanArgs.needsAsanRt() && SanArgs.needsSharedAsanRt()) {
+  if (SanArgs.needsSharedRt()) {
+    if (SanArgs.needsAsanRt()) {
       SharedRuntimes.push_back("asan");
+      if (!Args.hasArg(options::OPT_shared) && !TC.getTriple().isAndroid())
+        HelperStaticRuntimes.push_back("asan-preinit");
+    }
+
+    if (SanArgs.needsUbsanRt()) {
+      if (SanArgs.requiresMinimalRuntime()) {
+        SharedRuntimes.push_back("ubsan_minimal");
+      } else {
+        SharedRuntimes.push_back("ubsan_standalone");
+      }
+    }
   }
 
   // The stats_client library is also statically linked into DSOs.
   if (SanArgs.needsStatsRt())
     StaticRuntimes.push_back("stats_client");
 
   // Collect static runtimes.
-  if (Args.hasArg(options::OPT_shared) || TC.getTriple().isAndroid()) {
-    // Don't link static runtimes into DSOs or if compiling for Android.
+  if (Args.hasArg(options::OPT_shared) || SanArgs.needsSharedRt()) {
+    // Don't link static runtimes into DSOs or if -shared-libasan.
     return;
   }
   if (SanArgs.needsAsanRt()) {
-    if (SanArgs.needsSharedAsanRt()) {
-      HelperStaticRuntimes.push_back("asan-preinit");
-    } else {
-      StaticRuntimes.push_back("asan");
-      if (SanArgs.linkCXXRuntimes())
-        StaticRuntimes.push_back("asan_cxx");
-    }
-  }
   if (SanArgs.needsDfsanRt())
     StaticRuntimes.push_back("dfsan");
   if (SanArgs.needsLsanRt())
     StaticRuntimes.push_back("lsan");
   if (SanArgs.needsMsanRt()) {
     StaticRuntimes.push_back("msan");
     if (SanArgs.linkCXXRuntimes())
       StaticRuntimes.push_back("msan_cxx");

clang/lib/Driver/ToolChains/Fuchsia.cpp

void fuchsia::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   if (Args.hasArg(options::OPT_static))
     CmdArgs.push_back("-Bstatic");
   else if (Args.hasArg(options::OPT_shared))
     CmdArgs.push_back("-shared");
 
   if (!Args.hasArg(options::OPT_shared)) {
     std::string Dyld = D.DyldPrefix;
     if (ToolChain.getSanitizerArgs().needsAsanRt() &&
-        ToolChain.getSanitizerArgs().needsSharedAsanRt())
+        ToolChain.getSanitizerArgs().needsSharedRt())
       Dyld += "asan/";
     Dyld += "ld.so.1";
     CmdArgs.push_back("-dynamic-linker");
     CmdArgs.push_back(Args.MakeArgString(Dyld));
   }
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());

clang/lib/Driver/ToolChains/MSVC.cpp

if (DLL) {
     SmallString<128> ImplibName(Output.getFilename());
     llvm::sys::path::replace_extension(ImplibName, "lib");
     CmdArgs.push_back(Args.MakeArgString(std::string("-implib:") + ImplibName));
   }
 
   if (TC.getSanitizerArgs().needsAsanRt()) {
     CmdArgs.push_back(Args.MakeArgString("-debug"));
     CmdArgs.push_back(Args.MakeArgString("-incremental:no"));
-    if (TC.getSanitizerArgs().needsSharedAsanRt() ||
+    if (TC.getSanitizerArgs().needsSharedRt() ||
         Args.hasArg(options::OPT__SLASH_MD, options::OPT__SLASH_MDd)) {
       for (const auto &Lib : {"asan_dynamic", "asan_dynamic_runtime_thunk"})
         CmdArgs.push_back(TC.getCompilerRTArgString(Args, Lib));
       // Make sure the dynamic runtime thunk is not optimized out at link time
       // to ensure proper SEH handling.
       CmdArgs.push_back(Args.MakeArgString(
           TC.getArch() == llvm::Triple::x86
               ? "-include:___asan_seh_interceptor"

clang/test/Driver/sanitizer-ld.c

 // CHECK-ASAN-LINUX-NOT: "-export-dynamic"
 // CHECK-ASAN-LINUX: "--dynamic-list={{.*}}libclang_rt.asan-i386.a.syms"
 // CHECK-ASAN-LINUX-NOT: "-export-dynamic"
 // CHECK-ASAN-LINUX: "-lpthread"
 // CHECK-ASAN-LINUX: "-lrt"
 // CHECK-ASAN-LINUX: "-ldl"
 
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address -shared-libsan \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-SHARED-ASAN-LINUX %s
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address -shared-libasan \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-SHARED-ASAN-LINUX %s
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address \
+// RUN:     -shared-libsan -static-libsan -shared-libasan             \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-SHARED-ASAN-LINUX %s
 //
 // CHECK-SHARED-ASAN-LINUX: "{{(.*[^-.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-SHARED-ASAN-LINUX-NOT: "-lc"
 // CHECK-SHARED-ASAN-LINUX-NOT: libclang_rt.asan-i386.a"
 // CHECK-SHARED-ASAN-LINUX: libclang_rt.asan-i386.so"
 // CHECK-SHARED-ASAN-LINUX: "-whole-archive" "{{.*}}libclang_rt.asan-preinit-i386.a" "-no-whole-archive"
 // CHECK-SHARED-ASAN-LINUX-NOT: "-lpthread"
 // CHECK-SHARED-ASAN-LINUX-NOT: "-lrt"
 // CHECK-SHARED-ASAN-LINUX-NOT: "-ldl"
 // CHECK-SHARED-ASAN-LINUX-NOT: "-export-dynamic"
 // CHECK-SHARED-ASAN-LINUX-NOT: "--dynamic-list"
 
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.so -shared 2>&1 \
-// RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address -shared-libasan \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld -fsanitize=address -shared-libsan \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-DSO-SHARED-ASAN-LINUX %s
 //
 // CHECK-DSO-SHARED-ASAN-LINUX: "{{(.*[^-.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-DSO-SHARED-ASAN-LINUX-NOT: "-lc"
 // CHECK-DSO-SHARED-ASAN-LINUX-NOT: libclang_rt.asan-i386.a"
 // CHECK-DSO-SHARED-ASAN-LINUX-NOT: "libclang_rt.asan-preinit-i386.a"

 // RUN:   | FileCheck --check-prefix=CHECK-ASAN-ANDROID %s
 //
 // CHECK-ASAN-ANDROID: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-ASAN-ANDROID-NOT: "-lc"
 // CHECK-ASAN-ANDROID: "-pie"
 // CHECK-ASAN-ANDROID-NOT: "-lpthread"
 // CHECK-ASAN-ANDROID: libclang_rt.asan-arm-android.so"
 // CHECK-ASAN-ANDROID-NOT: "-lpthread"
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target arm-linux-androideabi -fuse-ld=ld -fsanitize=address \
+// RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
+// RUN:     -static-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-ASAN-ANDROID-STATICLIBASAN %s
+//
+// CHECK-ASAN-ANDROID-STATICLIBASAN: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
+// CHECK-ASAN-ANDROID-STATICLIBASAN: libclang_rt.asan-arm-android.a"
+// CHECK-ASAN-ANDROID-STATICLIBASAN: "-lpthread"
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target arm-linux-androideabi -fuse-ld=ld -fsanitize=undefined \
+// RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-ANDROID %s
+//
+// CHECK-UBSAN-ANDROID: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
+// CHECK-UBSAN-ANDROID-NOT: "-lc"
+// CHECK-UBSAN-ANDROID-NOT: "-pie"
+// CHECK-UBSAN-ANDROID-NOT: "-lpthread"
+// CHECK-UBSAN-ANDROID: libclang_rt.ubsan_standalone-arm-android.so"
+// CHECK-UBSAN-ANDROID-NOT: "-lpthread"
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target arm-linux-androideabi -fuse-ld=ld -fsanitize=undefined \
+// RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
+// RUN:     -static-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-ANDROID-STATICLIBASAN %s
+//
+// CHECK-UBSAN-ANDROID-STATICLIBASAN: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
+// CHECK-UBSAN-ANDROID-STATICLIBASAN: libclang_rt.ubsan_standalone-arm-android.a"
+// CHECK-UBSAN-ANDROID-STATICLIBASAN: "-lpthread"
+
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target i686-linux-android -fuse-ld=ld -fsanitize=address \
 // RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
 // RUN:   | FileCheck --check-prefix=CHECK-ASAN-ANDROID-X86 %s
 //
 // CHECK-ASAN-ANDROID-X86: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-ASAN-ANDROID-X86-NOT: "-lc"
 // CHECK-ASAN-ANDROID-X86: "-pie"
 // CHECK-ASAN-ANDROID-X86-NOT: "-lpthread"
 // CHECK-ASAN-ANDROID-X86: libclang_rt.asan-i686-android.so"
 // CHECK-ASAN-ANDROID-X86-NOT: "-lpthread"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target arm-linux-androideabi -fsanitize=address \
 // RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
-// RUN:     -shared-libasan \
+// RUN:     -shared-libsan \
 // RUN:   | FileCheck --check-prefix=CHECK-ASAN-ANDROID-SHARED-LIBASAN %s
 //
-// CHECK-ASAN-ANDROID-SHARED-LIBASAN-NOT: argument unused during compilation: '-shared-libasan'
+// CHECK-ASAN-ANDROID-SHARED-LIBASAN-NOT: argument unused during compilation: '-shared-libsan'
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target arm-linux-androideabi -fuse-ld=ld -fsanitize=address \
 // RUN:     --sysroot=%S/Inputs/basic_android_tree/sysroot \
 // RUN:     -shared \
 // RUN:   | FileCheck --check-prefix=CHECK-ASAN-ANDROID-SHARED %s
 //
 // CHECK-ASAN-ANDROID-SHARED: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"

 // CHECK-MSAN-LINUX-CXX: "-lpthread"
 // CHECK-MSAN-LINUX-CXX: "-lrt"
 // CHECK-MSAN-LINUX-CXX: "-ldl"
 
 // RUN: %clang -fsanitize=undefined %s -### -o %t.o 2>&1 \
 // RUN:     -target i386-unknown-linux -fuse-ld=ld \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX %s
+
+// RUN: %clang -fsanitize=undefined %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:     -static-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX %s
+
 // CHECK-UBSAN-LINUX: "{{.*}}ld{{(.exe)?}}"
 // CHECK-UBSAN-LINUX-NOT: libclang_rt.asan
 // CHECK-UBSAN-LINUX-NOT: libclang_rt.ubsan_standalone_cxx
 // CHECK-UBSAN-LINUX: "-whole-archive" "{{.*}}libclang_rt.ubsan_standalone-i386.a" "-no-whole-archive"
 // CHECK-UBSAN-LINUX-NOT: libclang_rt.asan
 // CHECK-UBSAN-LINUX-NOT: libclang_rt.ubsan_standalone_cxx
 // CHECK-UBSAN-LINUX-NOT: "-lstdc++"
 // CHECK-UBSAN-LINUX: "-lpthread"
 
+// RUN: %clang -fsanitize=undefined %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:     -shared-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX-SHAREDLIBASAN %s
+
+// RUN: %clang -fsanitize=undefined %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:     -static-libsan -shared-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX-SHAREDLIBASAN %s
+
+// RUN: %clang -fsanitize=undefined %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-unknown-linux -fuse-ld=ld \
+// RUN:     --sysroot=%S/Inputs/basic_linux_tree \
+// RUN:     -shared -shared-libsan \
+// RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX-SHAREDLIBASAN %s
+
+// CHECK-UBSAN-LINUX-SHAREDLIBASAN: "{{.*}}ld{{(.exe)?}}"
+// CHECK-UBSAN-LINUX-SHAREDLIBASAN: "{{.*}}libclang_rt.ubsan_standalone-i386.so{{.*}}"
+
 // RUN: %clang -fsanitize=undefined -fsanitize-link-c++-runtime %s -### -o %t.o 2>&1 \
 // RUN:     -target i386-unknown-linux \
 // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-UBSAN-LINUX-LINK-CXX %s
 // CHECK-UBSAN-LINUX-LINK-CXX-NOT: "-lstdc++"
 // CHECK-UBSAN-LINUX-LINK-CXX: "-whole-archive" "{{.*}}libclang_rt.ubsan_standalone_cxx-i386.a" "-no-whole-archive"
 // CHECK-UBSAN-LINUX-LINK-CXX-NOT: "-lstdc++"