Fix C++ support on recent DragonFly BSD releases

[dim]

Summary

[ Copied from https://llvm.org/bugs/show_bug.cgi?id=25597 ]

Clang support for DragonFly BSD is lagging a bit, resulting in poor
support for c++.

DragonFlyBSD is unique in that it has two base compilers. At the time
of the last Clang update for DragonFly, these compilers were GCC 4.4 and
GCC 4.7 (default).

With DragonFly Release 4.2, GCC 4.4 was replaced with GCC 5.0, partially
because the C++11 support of GCC 4.7 was incomplete. The DragonFly
project will Release version 4.4 soon.

This patch updates the Clang driver to use libstdc++ from GCC 5.2 The
support for falling back to the alternate compiler was removed for two
reasons:

1. The last release to use GCC 4.7 is DF 4.0 which has already reached EOL
2. GCC 4.7 libstdc++ is insufficient for many "ports"

Therefore, I think it is reasonable that the development version of
clang expects GCC 5.2 to be in place and not try to fall back to another
compiler.

The attached patch will do this. The Tools.cpp file was signficantly
modified to fix the linking which had been changed somewhere along the
line. The rest of the changes should be self-explanatory.

[davide]

The patch looks good, and the changes are localized to the DflyBSD driver so if you tested and works, I'm fine with it. I'll comit that unless objections rise.

[jrmarino]

Hi, can someone take a look at D15166?
It's a simple patch but critical for DragonFly.

[jrmarino]

Hi Davide,

Yes, the patch is tested it. We are carrying them in FreeBSD ports (which DragonFly uses), so they are being used now.

[dim]

Tried this with trunk r256465, but I get the following test failure:

    FAIL: Clang :: Driver/dragonfly.c (3997 of 30174)
    ******************** TEST 'Clang :: Driver/dragonfly.c' FAILED ********************
    Script:
    --
    /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/clang  -no-canonical-prefixes -target x86_64-pc-dragonfly /share/dim/src/llvm/trunk/tools/clang/test/Driver/dragonfly.c -### 2> /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/tools/clang/test/Driver/Output/dragonfly.c.tmp.log
    /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/FileCheck -input-file /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/tools/clang/test/Driver/Output/dragonfly.c.tmp.log /share/dim/src/llvm/trunk/tools/clang/test/Driver/dragonfly.c
    --
    Exit Code: 1

    Command Output (stderr):
    --
    /share/dim/src/llvm/trunk/tools/clang/test/Driver/dragonfly.c:5:11: error: expected string not found in input
    // CHECK: ld{{.*}}" "--eh-frame-hdr" "-dynamic-linker" "/usr/libexec/ld-elf.so.{{.*}}" "--hash-style=gnu" "-o" "a.out" "{{.*}}crt1.o" "{{.*}}crti.o" "{{.*}}crtbegin.o" "{{.*}}.o" "-L{{.*}}gcc{{.*}}" "-rpath" "{{.*}}gcc{{.*}}" "-lc" "-lgcc" "{{.*}}crtend.o" "{{.*}}crtn.o"
	      ^
    /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/tools/clang/test/Driver/Output/dragonfly.c.tmp.log:5:115: note: scanning from here
     "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/clang" "-cc1" "-triple" "x86_64-pc-dragonfly" "-emit-obj" "-mrelax-all" "-disable-free" "-main-file-name" "dragonfly.c" "-mrelocation-model" "static" "-mthread-model" "posix" "-mdisable-fp-elim" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-target-cpu" "x86-64" "-dwarf-column-info" "-debugger-tuning=gdb" "-resource-dir" "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/../lib/clang/3.8.0" "-fdebug-compilation-dir" "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/tools/clang/test/Driver" "-ferror-limit" "19" "-fmessage-length" "0" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-o" "/tmp/dragonfly-a045e8.o" "-x" "c" "/share/dim/src/llvm/trunk/tools/clang/test/Driver/dragonfly.c"
														      ^

@jrmarino, any idea? The actual output of the script was:

clang version 3.8.0 (trunk 256465)
Target: x86_64-pc-dragonfly
Thread model: posix
InstalledDir: /home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin
 "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/clang" "-cc1" "-triple" "x86_64-pc-dragonfly" "-emit-obj" "-mrelax-all" "-disable-free" "-main-file-name" "dragonfly.c" "-mrelocation-model" "static" "-mthread-model" "posix" "-mdisable-fp-elim" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-target-cpu" "x86-64" "-dwarf-column-info" "-debugger-tuning=gdb" "-resource-dir" "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/./bin/../lib/clang/3.8.0" "-fdebug-compilation-dir" "/home/dim/obj/llvm-256465M-trunk-freebsd11-i386-ninja-rel-1/tools/clang/test/Driver" "-ferror-limit" "19" "-fmessage-length" "0" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-o" "/tmp/dragonfly-a045e8.o" "-x" "c" "/share/dim/src/llvm/trunk/tools/clang/test/Driver/dragonfly.c"
 "/usr/local/bin/ld" "--eh-frame-hdr" "-dynamic-linker" "/usr/libexec/ld-elf.so.2" "--hash-style=gnu" "--enable-new-dtags" "-o" "a.out" "/usr/lib/crt1.o" "/usr/lib/crti.o" "/usr/lib/crtbegin.o" "/tmp/dragonfly-a045e8.o" "-L/usr/lib/gcc50" "-rpath" "/usr/lib/gcc50" "-lc" "-lgcc" "--as-needed" "-lgcc_pic" "--no-as-needed" "/usr/lib/crtend.o" "/usr/lib/crtn.o"

[dim]

Fix the test to check for --enable-new-dtags.

[tuxillo]

This comment was removed by tuxillo.

lib/Driver/ToolChains.cpp

DragonFly::DragonFly(const Driver &D, const llvm::Triple &Triple,
 
   // Path mangling to find libexec
   getProgramPaths().push_back(getDriver().getInstalledDir());
   if (getDriver().getInstalledDir() != getDriver().Dir)
     getProgramPaths().push_back(getDriver().Dir);
 
   getFilePaths().push_back(getDriver().Dir + "/../lib");
   getFilePaths().push_back("/usr/lib");
-  if (D.getVFS().exists("/usr/lib/gcc47"))
-    getFilePaths().push_back("/usr/lib/gcc47");
-  else
-    getFilePaths().push_back("/usr/lib/gcc44");
+  getFilePaths().push_back("/usr/lib/gcc50");
 }
 
 Tool *DragonFly::buildAssembler() const {
   return new tools::dragonfly::Assembler(*this);
 }
 
 Tool *DragonFly::buildLinker() const {
   return new tools::dragonfly::Linker(*this);

lib/Driver/Tools.cpp

 
 void dragonfly::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                      const InputInfo &Output,
                                      const InputInfoList &Inputs,
                                      const ArgList &Args,
                                      const char *LinkingOutput) const {
   const Driver &D = getToolChain().getDriver();
   ArgStringList CmdArgs;
-  bool UseGCC47 = llvm::sys::fs::exists("/usr/lib/gcc47");
 
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
   CmdArgs.push_back("--eh-frame-hdr");
   if (Args.hasArg(options::OPT_static)) {
     CmdArgs.push_back("-Bstatic");
   } else {
     if (Args.hasArg(options::OPT_rdynamic))
       CmdArgs.push_back("-export-dynamic");
     if (Args.hasArg(options::OPT_shared))
       CmdArgs.push_back("-Bshareable");
     else {
       CmdArgs.push_back("-dynamic-linker");
       CmdArgs.push_back("/usr/libexec/ld-elf.so.2");
     }
-    CmdArgs.push_back("--hash-style=both");
+    CmdArgs.push_back("--hash-style=gnu");
+    CmdArgs.push_back("--enable-new-dtags");
   }
 
   // When building 32-bit code on DragonFly/pc64, we have to explicitly
   // instruct ld in the base system to link 32-bit code.
   if (getToolChain().getArch() == llvm::Triple::x86) {
     CmdArgs.push_back("-m");
     CmdArgs.push_back("elf_i386");
   }
void dragonfly::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   Args.AddAllArgs(CmdArgs,
                   {options::OPT_L, options::OPT_T_Group, options::OPT_e});
 
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
-    // FIXME: GCC passes on -lgcc, -lgcc_pic and a whole lot of
-    //         rpaths
-    if (UseGCC47)
-      CmdArgs.push_back("-L/usr/lib/gcc47");
-    else
-      CmdArgs.push_back("-L/usr/lib/gcc44");
+    CmdArgs.push_back("-L/usr/lib/gcc50");
 
     if (!Args.hasArg(options::OPT_static)) {
-      if (UseGCC47) {
-        CmdArgs.push_back("-rpath");
-        CmdArgs.push_back("/usr/lib/gcc47");
-      } else {
-        CmdArgs.push_back("-rpath");
-        CmdArgs.push_back("/usr/lib/gcc44");
-      }
+      CmdArgs.push_back("/usr/lib/gcc50");
     }
 
     if (D.CCCIsCXX()) {
       getToolChain().AddCXXStdlibLibArgs(Args, CmdArgs);
       CmdArgs.push_back("-lm");
     }
 
     if (Args.hasArg(options::OPT_pthread))
       CmdArgs.push_back("-lpthread");
 
     if (!Args.hasArg(options::OPT_nolibc)) {
       CmdArgs.push_back("-lc");
     }
 
-    if (UseGCC47) {
-      if (Args.hasArg(options::OPT_static) ||
-          Args.hasArg(options::OPT_static_libgcc)) {
         CmdArgs.push_back("-lgcc");
         CmdArgs.push_back("-lgcc_eh");
-      } else {
-        if (Args.hasArg(options::OPT_shared_libgcc)) {
           CmdArgs.push_back("-lgcc_pic");
           if (!Args.hasArg(options::OPT_shared))
             CmdArgs.push_back("-lgcc");
-        } else {
           CmdArgs.push_back("-lgcc");
           CmdArgs.push_back("--as-needed");
           CmdArgs.push_back("-lgcc_pic");
           CmdArgs.push_back("--no-as-needed");
-        }
-      }
-    } else {
-      if (Args.hasArg(options::OPT_shared)) {
-        CmdArgs.push_back("-lgcc_pic");
-      } else {
-        CmdArgs.push_back("-lgcc");
-      }
-    }
   }
 
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     if (Args.hasArg(options::OPT_shared) || Args.hasArg(options::OPT_pie))
       CmdArgs.push_back(
           Args.MakeArgString(getToolChain().GetFilePath("crtendS.o")));
     else
       CmdArgs.push_back(

lib/Frontend/InitHeaderSearch.cpp

case llvm::Triple::Cygnus:
       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
       // g++-4 / Cygwin-1.5
       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
       break;
     }
     break;
   case llvm::Triple::DragonFly:
-    if (llvm::sys::fs::exists("/usr/lib/gcc47"))
-      AddPath("/usr/include/c++/4.7", CXXSystem, false);
-    else
-      AddPath("/usr/include/c++/4.4", CXXSystem, false);
+    AddPath("/usr/include/c++/5.0", CXXSystem, false);
     break;
   case llvm::Triple::OpenBSD: {
     std::string t = triple.getTriple();
     if (t.substr(0, 6) == "x86_64")
       t.replace(0, 6, "amd64");
     AddGnuCPlusPlusIncludePaths("/usr/include/g++",
                                 t, "", "", triple);
     break;

test/Driver/dragonfly.c

 // RUN: %clang -no-canonical-prefixes -target x86_64-pc-dragonfly %s -### 2> %t.log
 // RUN: FileCheck -input-file %t.log %s
 
 // CHECK: clang{{.*}}" "-cc1" "-triple" "x86_64-pc-dragonfly"
-// CHECK: ld{{.*}}" "--eh-frame-hdr" "-dynamic-linker" "/usr/libexec/ld-elf.so.{{.*}}" "--hash-style=both" "-o" "a.out" "{{.*}}crt1.o" "{{.*}}crti.o" "{{.*}}crtbegin.o" "{{.*}}.o" "-L{{.*}}gcc4{{.*}}" "-rpath" "{{.*}}gcc4{{.*}}" "-lc" "-lgcc" "{{.*}}crtend.o" "{{.*}}crtn.o"
+// CHECK: ld{{.*}}" "--eh-frame-hdr" "-dynamic-linker" "/usr/libexec/ld-elf.so.{{.*}}" "--hash-style=gnu" "-o" "a.out" "{{.*}}crt1.o" "{{.*}}crti.o" "{{.*}}crtbegin.o" "{{.*}}.o" "-L{{.*}}gcc{{.*}}" "-rpath" "{{.*}}gcc{{.*}}" "-lc" "-lgcc" "{{.*}}crtend.o" "{{.*}}crtn.o"