[Clang] Implement basic MinGW32 version-independent installation detection

[yaron.keren]

Summary

Adds a basic MinGW32 driver to Clang with GCC-version-independent installation detection that enables building using MinGW in non-hardcoded paths.

As there were breaking changes in trunk, the diff submitted is for release 3.4 as I am unable to build trunk with or without it (and therefore unable to test it). At the moment the patch will not, by default, search "C:\MinGW" as was the old behaviour. However, if necessary, implementing it should be trivial.

This implementation does inherit from Generic_GCC. It successfully detects GCC version 4.8.1 on Windows 7 x64 when given a sysroot of "C:\MinGW\x86_64-posix-4.8.1-rev5" (I should emphasise that the "4.8.1" is not derived from the the directory name).

[yaron.keren]

The patch must work with trunk to be accepted. The breaking changes are probably MinGW not being an OS anymore but an environment, you can test for it using isWindowsGNUEnvironment().

Have you compared to http://reviews.llvm.org/D3420 by martell/ruben ?

[• CJKay]

In D4177#4, @yaron.keren wrote:

The patch must work with trunk to be accepted. The breaking changes are probably MinGW not being an OS anymore but an environment, you can test for it using isWindowsGNUEnvironment().

Have you compared to http://reviews.llvm.org/D3420 by martell/ruben ?

I'm afraid someone else will have to patch it for release then. I can't get trunk to build at all with or without the patch due to some major changes in the build system that I've been unsuccessful in patching for my system.

I have taken a look at ruben's patch but not extending Generic_GCC causes it to be significantly more complex than it needs to be as most of the logic can be transferred, contrary to what he states. It still uses hardcoded paths whereas this patch uses Generic_GCCs version detection.

When I can get a working trunk build I'll give a shot at updating the patch.

[yaron.keren]

What are the problems with the build system? are you using cmake?

[• CJKay]

In D4177#7, @yaron.keren wrote:

What are the problems with the build system? are you using cmake?

I am. It seems add_{clang,llvm}_library() macros were added, but as of yet the rest of the project has not been updated to use them properly. This results in a lot of CMake policy warnings, and about 98% into the build process, I get missing reference errors inside liblibClang.a when trying to build diagtool.exe. I have so far not had much luck in fixing this for myself, as I am fairly uneducated on the changes introduced, and it doesn't look as if I can temporarily disable building diagtool. I can submit a bug report if you wish, as I can still build release 3.4 smoothly.

[yaron.keren]

You can disable building the tools with -DLLVM_BUILD_TOOLS=OFF on the CMake command line.
More build options: http://llvm.org/docs/CMake.html

I am building LLVM with Visual C++ 2013 routinely and I think one of the build bots does use MinGW.
Which compiler are you using? MinGW? which version?

[• CJKay]

In D4177#9, @yaron.keren wrote:

You can disable building the tools with -DLLVM_BUILD_TOOLS=OFF on the CMake command line.
More build options: http://llvm.org/docs/CMake.html

I am building LLVM with Visual C++ 2013 routinely and I think one of the build bots does use MinGW.
Which compiler are you using? MinGW? which version?

Edit: build complete.

Updating for trunk is proving difficult, but I will update this thread with the diff when I work around the environment/OS switcharoo.

[• rafael]

What is the status on this? It would be really nice to drop the hardcoded paths.

[• CJKay]

In D4177#11, @rafael wrote:

What is the status on this? It would be really nice to drop the hardcoded paths.

Sadly, I don't currently have the free time to work on this at the moment. The code that I posted so far needs to be reworked for current trunk but I don't reckon I know enough about LLVM's internals to properly update it either way as there were some fairly substantial changes.
If no progress has been made over the next few months I could perhaps speak to my manager about dedicating some of my time to it, but I've no idea how well that would go down.

[yaron.keren]

Superceded by http://reviews.llvm.org/D5268

lib/Driver/Driver.cpp

       TC = new toolchains::Windows(*this, Target, Args);
       break;
     case llvm::Triple::MinGW32:
-      // FIXME: We need a MinGW toolchain. Fallthrough for now.
+      TC = new toolchains::MinGW32(*this, Target, Args);
+      break;
     default:
       // TCE is an OSless target
       if (Target.getArchName() == "tce") {

lib/Driver/ToolChains.h

                                    llvm::opt::ArgStringList &CmdArgs) const;
 };
 
+class LLVM_LIBRARY_VISIBILITY MinGW32 : public Generic_GCC {
+public:
+  MinGW32(const Driver &D, const llvm::Triple &Triple,
+          const llvm::opt::ArgList &Args);
+  
+  virtual bool IsUnwindTablesDefault() const { return getArch() == llvm::Triple::x86_64; }
+  virtual bool isPICDefault() const { return getArch() == llvm::Triple::x86_64; }
+  virtual bool isPICDefaultForced() const { return getArch() == llvm::Triple::x86_64; }
+  virtual bool isPIEDefault() const { return false; }
+  
+  virtual void AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                                         llvm::opt::ArgStringList &CC1Args) const;
+  virtual void AddClangCXXStdlibIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                                            llvm::opt::ArgStringList &CC1Args) const;
+};
+
 } // end namespace toolchains
 } // end namespace driver
 } // end namespace clang

lib/Driver/ToolChains.cpp

                                  LI->path() + MIPSABIDirSuffix,
                                  TargetArch, Args)) {
         GCCBiarchSuffix = BiarchSuffix;
-      } else if (NeedsBiarchSuffix ||
-                 !hasCrtBeginObj(LI->path() + MIPSABIDirSuffix)) {
+      } else if (NeedsBiarchSuffix || (
+                  !hasCrtBeginObj(LI->path() + MIPSABIDirSuffix) &&
+                  !CandidateTriple.endswith("-mingw32")
+                )) {
+        // FIXME: MinGW doesn't hold crtbegin.o here
+        // Maybe there's another file we can search for instead?
         continue;
       } else {
         GCCBiarchSuffix.clear();

                                 ArgStringList &CmdArgs) const {
   // We don't output any lib args. This is handled by xcc.
 }
+
+/// MinGW32 - MinGW32 toolchain (experimental).
+
+MinGW32::MinGW32(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
+  : Generic_GCC(D, Triple, Args) {
+
+#if defined(_WIN32)
+  getFilePaths().push_back(D.SysRoot + "/lib");
+  getFilePaths().push_back(D.SysRoot + "/" + Triple.getTriple() + "/lib");
+#else
+  getFilePaths().push_back(D.SysRoot + "/usr/lib");
+  getFilePaths().push_back(D.SysRoot + "/usr/" + Triple.getTriple() + "/lib");
+#endif
+}
+
+void MinGW32::AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                                        llvm::opt::ArgStringList &CC1Args) const {
+  if(DriverArgs.hasArg(options::OPT_nostdinc) ||
+     DriverArgs.hasArg(options::OPT_nostdlibinc))
+    return;
+
+#if defined(_WIN32)
+  addSystemInclude(DriverArgs, CC1Args,
+                   getDriver().SysRoot + "/" + getTriple().getTriple() + "/include");
+#else
+  addSystemInclude(DriverArgs, CC1Args,
+                   getDriver().SysRoot + "/usr/" + getTriple().getTriple() + "/include");
+#endif
+}
+
+void MinGW32::AddClangCXXStdlibIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                                           llvm::opt::ArgStringList &CC1Args) const {
+  if(DriverArgs.hasArg(options::OPT_nostdincxx) ||
+     DriverArgs.hasArg(options::OPT_nostdlibinc))
+     return;
+
+  if(GCCInstallation.isValid()) {
+    addSystemInclude(DriverArgs, CC1Args,
+                     GCCInstallation.getInstallPath() + "/include");
+    addSystemInclude(DriverArgs, CC1Args,
+                     GCCInstallation.getInstallPath() + "/include-fixed");
+    addSystemInclude(DriverArgs, CC1Args,
+                     GCCInstallation.getInstallPath() + "/include/c++");
+    addSystemInclude(DriverArgs, CC1Args,
+                     GCCInstallation.getInstallPath() + "/include/c++/" + getTriple().getTriple());
+  }
+}

lib/Frontend/InitHeaderSearch.cpp

     case llvm::Triple::NetBSD:
     case llvm::Triple::OpenBSD:
     case llvm::Triple::Bitrig:
+    case llvm::Triple::MinGW32:
       break;
     default:
       // FIXME: temporary hack: hard-coded paths.

   switch (os) {
   case llvm::Triple::Linux:
   case llvm::Triple::Win32:
+  case llvm::Triple::MinGW32:
     llvm_unreachable("Include management is handled in the driver.");
 
   case llvm::Triple::Haiku:

   case llvm::Triple::Cygwin:
     AddPath("/usr/include/w32api", System, false);
     break;
-  case llvm::Triple::MinGW32: { 
-      // mingw-w64 crt include paths
-      // <sysroot>/i686-w64-mingw32/include
-      SmallString<128> P = StringRef(HSOpts.ResourceDir);
-      llvm::sys::path::append(P, "../../../i686-w64-mingw32/include");
-      AddPath(P.str(), System, false);
-
-      // <sysroot>/x86_64-w64-mingw32/include
-      P.resize(HSOpts.ResourceDir.size());
-      llvm::sys::path::append(P, "../../../x86_64-w64-mingw32/include");
-      AddPath(P.str(), System, false);
-
-      // mingw.org crt include paths
-      // <sysroot>/include
-      P.resize(HSOpts.ResourceDir.size());
-      llvm::sys::path::append(P, "../../../include");
-      AddPath(P.str(), System, false);
-      AddPath("/mingw/include", System, false);
-#if defined(_WIN32)
-      AddPath("c:/mingw/include", System, false); 
-#endif
-    }
-    break;
       
   default:
     break;

   switch (os) {
   case llvm::Triple::Linux:
   case llvm::Triple::Win32:
+  case llvm::Triple::MinGW32:
     llvm_unreachable("Include management is handled in the driver.");
 
   case llvm::Triple::Cygwin:

     // g++-4 / Cygwin-1.5
     AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
     break;
-  case llvm::Triple::MinGW32:
-    // mingw-w64 C++ include paths (i686-w64-mingw32 and x86_64-w64-mingw32)
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.0");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.1");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.2");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.3");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.4");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.0");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.1");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.2");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.3");
-    AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.0");
-    // mingw.org C++ include paths
-    AddMinGWCPlusPlusIncludePaths("/mingw/lib/gcc", "mingw32", "4.5.2"); //MSYS
-#if defined(_WIN32)
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.8.1");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.6.2");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.6.1");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.5.2");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.5.0");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.4.0");
-    AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.3.0");
-#endif
-    break;
   case llvm::Triple::DragonFly:
     if (llvm::sys::fs::exists("/usr/lib/gcc47"))
       AddPath("/usr/include/c++/4.7", CXXSystem, false);

 
   case llvm::Triple::Linux:
   case llvm::Triple::Win32:
+  case llvm::Triple::MinGW32:
     return;
   }