Fix the -print-multi-directory flag to print the selected multilib.

[chrib]

Summary

Fix -print-multi-directory to print the selected multilib

[chrib]

https://bugs.llvm.org/show_bug.cgi?id=21360

[jroelofs]

LGTM. Thanks for fixing this!

[thakis]

The test fails on my system like so:

--

********************
FAIL: Clang :: Driver/print-multi-directory.c (4696 of 13174)
******************** TEST 'Clang :: Driver/print-multi-directory.c' FAILED ********************
Script:
--
: 'RUN: at line 1';   /usr/local/google/home/thakis/src/llvm-build-goma/bin/clang -no-canonical-prefixes /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c -### -o /usr/local/google/home/thakis/src/llvm-build-goma/tools/clang/test/Driver/Output/print-multi-directory.c.tmp.o 2>&1      -target i386-none-linux      -print-multi-directory    | /usr/local/google/home/thakis/src/llvm-build-goma/bin/FileCheck --check-prefix=CHECK-X86-MULTILIBS /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c
: 'RUN: at line 10';   /usr/local/google/home/thakis/src/llvm-build-goma/bin/clang -no-canonical-prefixes /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c -### -o /usr/local/google/home/thakis/src/llvm-build-goma/tools/clang/test/Driver/Output/print-multi-directory.c.tmp.o 2>&1      -target i386-none-linux -m64      -print-multi-directory    | /usr/local/google/home/thakis/src/llvm-build-goma/bin/FileCheck --check-prefix=CHECK-X86_64-MULTILIBS /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c
: 'RUN: at line 19';   /usr/local/google/home/thakis/src/llvm-build-goma/bin/clang -no-canonical-prefixes /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c -### -o /usr/local/google/home/thakis/src/llvm-build-goma/tools/clang/test/Driver/Output/print-multi-directory.c.tmp.o 2>&1      -target arm-linux-androideabi21 -stdlib=libstdc++      -mthumb      -B/usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/Inputs/basic_android_ndk_tree      --sysroot=/usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/Inputs/basic_android_ndk_tree/sysroot      -print-multi-directory    | /usr/local/google/home/thakis/src/llvm-build-goma/bin/FileCheck  --check-prefix=CHECK-ARM-MULTILIBS /usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c
--
Exit Code: 1

Command Output (stderr):
--
/usr/local/google/home/thakis/src/llvm-rw/tools/clang/test/Driver/print-multi-directory.c:6:25: error: CHECK-X86-MULTILIBS: expected string not found in input
// CHECK-X86-MULTILIBS: 32
                        ^
<stdin>:1:1: note: scanning from here
clang version 8.0.0 (trunk 341389)
^
<stdin>:1:28: note: possible intended match here
clang version 8.0.0 (trunk 341389)
                           ^

--

[timshen]

The test fails on my system like so:

I also observed the same failure.

Bots also fail: http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules/builds/19509/steps/check-all/logs/FAIL%3A%20Clang%3A%3Aprint-multi-directory.c

I'm going to revert this patch.

[chrib]

This comment was removed by chrib.

[cfe-commits]

Understood, The test worked for me because I have both 64 bit and 32 bit libs installed on my default sysroot. Otherwise might fail indeed.

Will amend the test with an explicit sysroot,

[chrib]

Re-commit patch at r341547 with modified test case to use an explicit root tree for libraries

[stella.stamenova]

I saw this test fail in our testing as well. I think the matches are too broad and I suspect this will fail intermittently on the bots too causing confusion:

Command Output (stderr):
--
/vstsdrive/_work/10/s/llvm/tools/clang/test/Driver/print-multi-directory.c:19:32: error: CHECK-X86_64-MULTILIBS-NOT: excluded string found in input
// CHECK-X86_64-MULTILIBS-NOT: 32
                               ^
<stdin>:1:199: note: found here
clang version 8.0.0 (https://[e-mail]/llvm/_git/clang 5df831d3873a0affc7c7e1d908978f68222737f1) (llvm/_git/llvm 3e62673386d63e53205e2b6b92955c5506225e38)
                                                                                                                                                                                                      ^~

include/clang/Driver/ToolChain.h

private:
 
   /// Set the toolchain's effective clang triple.
   void setEffectiveTriple(llvm::Triple ET) const {
     EffectiveTriple = std::move(ET);
   }
 
 protected:
   MultilibSet Multilibs;
+  Multilib SelectedMultilib;
 
   ToolChain(const Driver &D, const llvm::Triple &T,
             const llvm::opt::ArgList &Args);
 
   void setTripleEnvironment(llvm::Triple::EnvironmentType Env);
 
   virtual Tool *buildAssembler() const;
   virtual Tool *buildLinker() const;
public:
   path_list &getFilePaths() { return FilePaths; }
   const path_list &getFilePaths() const { return FilePaths; }
 
   path_list &getProgramPaths() { return ProgramPaths; }
   const path_list &getProgramPaths() const { return ProgramPaths; }
 
   const MultilibSet &getMultilibs() const { return Multilibs; }
 
+  const Multilib &getMultilib() const { return SelectedMultilib; }
+
   const SanitizerArgs& getSanitizerArgs() const;
 
   const XRayArgs& getXRayArgs() const;
 
   // Returns the Arg * that explicitly turned on/off rtti, or nullptr.
   const llvm::opt::Arg *getRTTIArg() const { return CachedRTTIArg; }
 
   // Returns the RTTIMode for the toolchain with the current arguments.

lib/Driver/Driver.cpp

bool Driver::HandleImmediateArgs(const Compilation &C) {
 
   if (C.getArgs().hasArg(options::OPT_print_multi_lib)) {
     for (const Multilib &Multilib : TC.getMultilibs())
       llvm::outs() << Multilib << "\n";
     return false;
   }
 
   if (C.getArgs().hasArg(options::OPT_print_multi_directory)) {
-    for (const Multilib &Multilib : TC.getMultilibs()) {
-      if (Multilib.gccSuffix().empty())
-        llvm::outs() << ".\n";
-      else {
-        StringRef Suffix(Multilib.gccSuffix());
-        assert(Suffix.front() == '/');
-        llvm::outs() << Suffix.substr(1) << "\n";
-      }
-    }
+    const Multilib &Multilib = TC.getMultilib();
     return false;
   }
 
   if (C.getArgs().hasArg(options::OPT_print_target_triple)) {
     llvm::outs() << TC.getTripleString() << "\n";
     return false;
   }
 

lib/Driver/ToolChains/Linux.cpp

if (const auto &PathsCallback = Multilibs.filePathsCallback())
     for (const auto &Path : PathsCallback(Multilib))
       addPathIfExists(D, InstallPath + Path, Paths);
 }
 
 Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   GCCInstallation.init(Triple, Args);
   Multilibs = GCCInstallation.getMultilibs();
+  SelectedMultilib = GCCInstallation.getMultilib();
   llvm::Triple::ArchType Arch = Triple.getArch();
   std::string SysRoot = computeSysRoot();
 
   // Cross-compiling binutils and GCC installations (vanilla and openSUSE at
   // least) put various tools in a triple-prefixed directory off of the parent
   // of the GCC installation. We use the GCC triple here to ensure that we end
   // up with tools that support the same amount of cross compiling as the
   // detected GCC installation. For example, if we find a GCC installation
#endif
 
   const std::string OSLibDir = getOSLibDir(Triple, Args);
   const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
 
   // Add the multilib suffixed paths where they are available.
   if (GCCInstallation.isValid()) {
     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
     const std::string &LibPath = GCCInstallation.getParentLibPath();
-    const Multilib &Multilib = GCCInstallation.getMultilib();
-    const MultilibSet &Multilibs = GCCInstallation.getMultilibs();
 
     // Add toolchain / multilib specific file paths.
-    addMultilibsFilePaths(D, Multilibs, Multilib,
+    addMultilibsFilePaths(D, Multilibs, SelectedMultilib,
                           GCCInstallation.getInstallPath(), Paths);
 
     // Sourcery CodeBench MIPS toolchain holds some libraries under
     // a biarch-like suffix of the GCC installation.
-    addPathIfExists(D, GCCInstallation.getInstallPath() + Multilib.gccSuffix(),
+    addPathIfExists(D, GCCInstallation.getInstallPath() + SelectedMultilib.gccSuffix(),
                     Paths);
 
     // GCC cross compiling toolchains will install target libraries which ship
     // as part of the toolchain under <prefix>/<triple>/<libdir> rather than as
     // any part of the GCC installation in
     // <prefix>/<libdir>/gcc/<triple>/<version>. This decision is somewhat
     // debatable, but is the reality today. We need to search this tree even
     // when we have a sysroot somewhere else. It is the responsibility of
     // whomever is doing the cross build targeting a sysroot using a GCC
     // installation that is *not* within the system root to ensure two things:
     //
     //  1) Any DSOs that are linked in from this tree or from the install path
     //     above must be present on the system root and found via an
     //     appropriate rpath.
     //  2) There must not be libraries installed into
     //     <prefix>/<triple>/<libdir> unless they should be preferred over
     //     those within the system root.
     //
     // Note that this matches the GCC behavior. See the below comment for where
     // Clang diverges from GCC's behavior.
     addPathIfExists(D, LibPath + "/../" + GCCTriple.str() + "/lib/../" +
-                           OSLibDir + Multilib.osSuffix(),
+                           OSLibDir + SelectedMultilib.osSuffix(),
                     Paths);
 
     // If the GCC installation we found is inside of the sysroot, we want to
     // prefer libraries installed in the parent prefix of the GCC installation.
     // It is important to *not* use these paths when the GCC installation is
     // outside of the system root as that can pick up unintended libraries.
     // This usually happens when there is an external cross compiler on the
     // host system, and a more minimal sysroot available that is the target of

test/Driver/print-multi-directory.c

+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-none-linux \
+// RUN:     -print-multi-directory \
+// RUN:   | FileCheck --check-prefix=CHECK-X86-MULTILIBS %s
+
+// CHECK-X86-MULTILIBS:      32
+// CHECK-X86-MULTILIBS-NOT:  x32
+// CHECK-X86-MULTILIBS-NOT:  .
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target i386-none-linux -m64 \
+// RUN:     -print-multi-directory \
+// RUN:   | FileCheck --check-prefix=CHECK-X86_64-MULTILIBS %s
+
+// CHECK-X86_64-MULTILIBS:      .
+// CHECK-X86_64-MULTILIBS-NOT:  x32
+// CHECK-X86_64-MULTILIBS-NOT:  32
+
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     -target arm-linux-androideabi21 -stdlib=libstdc++ \
+// RUN:     -mthumb \
+// RUN:     -B%S/Inputs/basic_android_ndk_tree \
+// RUN:     --sysroot=%S/Inputs/basic_android_ndk_tree/sysroot \
+// RUN:     -print-multi-directory \
+// RUN:   | FileCheck  --check-prefix=CHECK-ARM-MULTILIBS %s
+
+// CHECK-ARM-MULTILIBS:      thumb
+// CHECK-ARM-MULTILIBS-NOT:  .