Add support for CPATH and friends.

This moves the existing code for CPATH into the driver and adds the environment lookup and path splitting there.
The paths are then passed down to cc1 with -I options (CPATH), added after the normal user-specified include dirs.
Language specific paths are passed via -LANG-isystem and the actual filtering is performed in the frontend.

I tried to match GCC's behavior as close as possible

Fixes PR8971.

llvm-svn: 140341

6 files changed, 115 insertions, 75 deletions

diff --git a/clang/include/clang/Driver/CC1Options.td b/clang/include/clang/Driver/CC1Options.td
index ba9469a9494..ad61f6a9f49 100644
--- a/clang/include/clang/Driver/CC1Options.td
+++ b/clang/include/clang/Driver/CC1Options.td
@@ -623,8 +623,16 @@ def index_header_map : Flag<"-index-header-map">,
   HelpText<"Make the next included directory (-I or -F) an indexer header map">;
 def iquote : JoinedOrSeparate<"-iquote">, MetaVarName<"<directory>">,
   HelpText<"Add directory to QUOTE include search path">;
+def c_isystem : JoinedOrSeparate<"-c-isystem">, MetaVarName<"<directory>">,
+  HelpText<"Add directory to the C SYSTEM include search path">;
 def cxx_isystem : JoinedOrSeparate<"-cxx-isystem">, MetaVarName<"<directory>">,
   HelpText<"Add directory to the C++ SYSTEM include search path">;
+def objc_isystem : JoinedOrSeparate<"-objc-isystem">,
+  MetaVarName<"<directory>">,
+  HelpText<"Add directory to the ObjC SYSTEM include search path">;
+def objcxx_isystem : JoinedOrSeparate<"-objcxx-isystem">,
+  MetaVarName<"<directory>">,
+  HelpText<"Add directory to the ObjC++ SYSTEM include search path">;
 def isystem : JoinedOrSeparate<"-isystem">, MetaVarName<"<directory>">,
   HelpText<"Add directory to SYSTEM include search path">;
 def iwithsysroot : JoinedOrSeparate<"-iwithsysroot">,MetaVarName<"<directory>">,
diff --git a/clang/include/clang/Frontend/HeaderSearchOptions.h b/clang/include/clang/Frontend/HeaderSearchOptions.h
index e0f80e3bdf3..39d31363745 100644
--- a/clang/include/clang/Frontend/HeaderSearchOptions.h
+++ b/clang/include/clang/Frontend/HeaderSearchOptions.h
@@ -26,7 +26,10 @@ namespace frontend {
     IndexHeaderMap, ///< Like Angled, but marks header maps used when
                        ///  building frameworks.
     System,         ///< Like Angled, but marks system directories.
+    CSystem,        ///< Like System, but only used for C.
     CXXSystem,      ///< Like System, but only used for C++.
+    ObjCSystem,     ///< Like System, but only used for ObjC.
+    ObjCXXSystem,   ///< Like System, but only used for ObjC++.
     After           ///< Like System, but searched after the system directories.
   };
 }
@@ -59,18 +62,6 @@ public:
   /// User specified include entries.
   std::vector<Entry> UserEntries;
 
-  /// A (system-path) delimited list of include paths to be added from the
-  /// environment following the user specified includes (but prior to builtin
-  /// and standard includes). This is parsed in the same manner as the CPATH
-  /// environment variable for gcc.
-  std::string EnvIncPath;
-
-  /// Per-language environmental include paths, see \see EnvIncPath.
-  std::string CEnvIncPath;
-  std::string ObjCEnvIncPath;
-  std::string CXXEnvIncPath;
-  std::string ObjCXXEnvIncPath;
-
   /// The directory which holds the compiler resource files (builtin includes,
   /// etc.).
   std::string ResourceDir;
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 840e4c27348..c3c07f412f8 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -183,6 +183,38 @@ static void addProfileRT(const ToolChain &TC, const ArgList &Args,
   CmdArgs.push_back(Args.MakeArgString(ProfileRT));
 }
 
+static void AddIncludeDirectoryList(const ArgList &Args,
+                                    ArgStringList &CmdArgs,
+                                    const char *ArgName,
+                                    const char *DirList) {
+  if (!DirList)
+    return; // Nothing to do.
+
+  StringRef Dirs(DirList);
+  if (Dirs.empty()) // Empty string should not add '.'.
+    return;
+
+  StringRef::size_type Delim;
+  while ((Delim = Dirs.find(llvm::sys::PathSeparator)) != StringRef::npos) {
+    if (Delim == 0) { // Leading colon.
+      CmdArgs.push_back(ArgName);
+      CmdArgs.push_back(".");
+    } else {
+      CmdArgs.push_back(ArgName);
+      CmdArgs.push_back(Args.MakeArgString(Dirs.substr(0, Delim)));
+    }
+    Dirs = Dirs.substr(Delim + 1);
+  }
+
+  if (Dirs.empty()) { // Trailing colon.
+    CmdArgs.push_back(ArgName);
+    CmdArgs.push_back(".");
+  } else { // Add the last path.
+    CmdArgs.push_back(ArgName);
+    CmdArgs.push_back(Args.MakeArgString(Dirs));
+  }
+}
+
 void Clang::AddPreprocessingOptions(const Driver &D,
                                     const ArgList &Args,
                                     ArgStringList &CmdArgs,
@@ -391,6 +423,23 @@ void Clang::AddPreprocessingOptions(const Driver &D,
   }
   
   Args.AddAllArgs(CmdArgs, options::OPT_fauto_module_import);
+
+  // Parse additional include paths from environment variables.
+  // CPATH - included following the user specified includes (but prior to
+  // builtin and standard includes).
+  AddIncludeDirectoryList(Args, CmdArgs, "-I", ::getenv("CPATH"));
+  // C_INCLUDE_PATH - system includes enabled when compiling C.
+  AddIncludeDirectoryList(Args, CmdArgs, "-c-isystem",
+                          ::getenv("C_INCLUDE_PATH"));
+  // CPLUS_INCLUDE_PATH - system includes enabled when compiling C++.
+  AddIncludeDirectoryList(Args, CmdArgs, "-cxx-isystem",
+                          ::getenv("CPLUS_INCLUDE_PATH"));
+  // OBJC_INCLUDE_PATH - system includes enabled when compiling ObjC.
+  AddIncludeDirectoryList(Args, CmdArgs, "-objc-isystem",
+                          ::getenv("OBJC_INCLUDE_PATH"));
+  // OBJCPLUS_INCLUDE_PATH - system includes enabled when compiling ObjC++.
+  AddIncludeDirectoryList(Args, CmdArgs, "-objcxx-isystem",
+                          ::getenv("OBJCPLUS_INCLUDE_PATH"));
 }
 
 /// getARMTargetCPU - Get the (LLVM) name of the ARM cpu we are targeting.
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 7cb707b9661..e6992613791 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -534,9 +534,21 @@ static void HeaderSearchOptsToArgs(const HeaderSearchOptions &Opts,
         Res.push_back(E.IsFramework? "-F" : "-I");
         break;
         
+      case frontend::CSystem:
+        Res.push_back("-c-isystem");
+        break;
+
       case frontend::CXXSystem:
         Res.push_back("-cxx-isystem");
         break;
+
+      case frontend::ObjCSystem:
+        Res.push_back("-objc-isystem");
+        break;
+
+      case frontend::ObjCXXSystem:
+        Res.push_back("-objcxx-isystem");
+        break;
         
       case frontend::Angled:
         Res.push_back(E.IsFramework ? "-F" : "-I");
@@ -551,26 +563,6 @@ static void HeaderSearchOptsToArgs(const HeaderSearchOptions &Opts,
     Res.push_back(E.Path);
   }
 
-  if (!Opts.EnvIncPath.empty()) {
-    // FIXME: Provide an option for this, and move env detection to driver.
-    llvm::report_fatal_error("Not yet implemented!");
-  }
-  if (!Opts.CEnvIncPath.empty()) {
-    // FIXME: Provide an option for this, and move env detection to driver.
-    llvm::report_fatal_error("Not yet implemented!");
-  }
-  if (!Opts.ObjCEnvIncPath.empty()) {
-    // FIXME: Provide an option for this, and move env detection to driver.
-    llvm::report_fatal_error("Not yet implemented!");
-  }
-  if (!Opts.CXXEnvIncPath.empty()) {
-    // FIXME: Provide an option for this, and move env detection to driver.
-    llvm::report_fatal_error("Not yet implemented!");
-  }
-  if (!Opts.ObjCXXEnvIncPath.empty()) {
-    // FIXME: Provide an option for this, and move env detection to driver.
-    llvm::report_fatal_error("Not yet implemented!");
-  }
   if (!Opts.ResourceDir.empty()) {
     Res.push_back("-resource-dir");
     Res.push_back(Opts.ResourceDir);
@@ -1424,14 +1416,25 @@ static void ParseHeaderSearchArgs(HeaderSearchOptions &Opts, ArgList &Args) {
   for (arg_iterator it = Args.filtered_begin(OPT_iquote),
          ie = Args.filtered_end(); it != ie; ++it)
     Opts.AddPath((*it)->getValue(Args), frontend::Quoted, true, false, false);
-  for (arg_iterator it = Args.filtered_begin(OPT_cxx_isystem, OPT_isystem,
+  for (arg_iterator it = Args.filtered_begin(OPT_isystem,
          OPT_iwithsysroot), ie = Args.filtered_end(); it != ie; ++it)
-    Opts.AddPath((*it)->getValue(Args),
-                 ((*it)->getOption().matches(OPT_cxx_isystem) ?
-                   frontend::CXXSystem : frontend::System),
-                 true, false, !(*it)->getOption().matches(OPT_iwithsysroot));
-  
-  // FIXME: Need options for the various environment variables!
+    Opts.AddPath((*it)->getValue(Args), frontend::System, true, false,
+                 !(*it)->getOption().matches(OPT_iwithsysroot));
+
+  // Add the paths for the various language specific isystem flags.
+  for (arg_iterator it = Args.filtered_begin(OPT_c_isystem),
+       ie = Args.filtered_end(); it != ie; ++it)
+    Opts.AddPath((*it)->getValue(Args), frontend::CSystem, true, false, true);
+  for (arg_iterator it = Args.filtered_begin(OPT_cxx_isystem),
+       ie = Args.filtered_end(); it != ie; ++it)
+    Opts.AddPath((*it)->getValue(Args), frontend::CXXSystem, true, false, true);
+  for (arg_iterator it = Args.filtered_begin(OPT_objc_isystem),
+       ie = Args.filtered_end(); it != ie; ++it)
+    Opts.AddPath((*it)->getValue(Args), frontend::ObjCSystem, true, false,true);
+  for (arg_iterator it = Args.filtered_begin(OPT_objcxx_isystem),
+       ie = Args.filtered_end(); it != ie; ++it)
+    Opts.AddPath((*it)->getValue(Args), frontend::ObjCXXSystem, true, false,
+                 true);
 }
 
 void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
diff --git a/clang/lib/Frontend/InitHeaderSearch.cpp b/clang/lib/Frontend/InitHeaderSearch.cpp
index 08af5322675..089ded19cef 100644
--- a/clang/lib/Frontend/InitHeaderSearch.cpp
+++ b/clang/lib/Frontend/InitHeaderSearch.cpp
@@ -81,10 +81,6 @@ public:
   void AddMinGW64CXXPaths(StringRef Base,
                           StringRef Version);
 
-  /// AddDelimitedPaths - Add a list of paths delimited by the system PATH
-  /// separator. The processing follows that of the CPATH variable for gcc.
-  void AddDelimitedPaths(StringRef String);
-
   // AddDefaultCIncludePaths - Add paths that should always be searched.
   void AddDefaultCIncludePaths(const llvm::Triple &triple,
                                const HeaderSearchOptions &HSOpts);
@@ -167,26 +163,6 @@ void InitHeaderSearch::AddPath(const Twine &Path,
                  << MappedPathStr << "\"\n";
 }
 
-
-void InitHeaderSearch::AddDelimitedPaths(StringRef at) {
-  if (at.empty()) // Empty string should not add '.' path.
-    return;
-
-  StringRef::size_type delim;
-  while ((delim = at.find(llvm::sys::PathSeparator)) != StringRef::npos) {
-    if (delim == 0)
-      AddPath(".", Angled, false, true, false);
-    else
-      AddPath(at.substr(0, delim), Angled, false, true, false);
-    at = at.substr(delim + 1);
-  }
-
-  if (at.empty())
-    AddPath(".", Angled, false, true, false);
-  else
-    AddPath(at, Angled, false, true, false);
-}
-
 void InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
                                                    StringRef ArchDir,
                                                    StringRef Dir32,
@@ -1094,7 +1070,11 @@ void InitHeaderSearch::Realize(const LangOptions &Lang) {
 
   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
        it != ie; ++it) {
-    if (it->first == System || (Lang.CPlusPlus && it->first == CXXSystem))
+    if (it->first == System ||
+        (!Lang.ObjC1 && !Lang.CPlusPlus && it->first == CSystem)    ||
+        (!Lang.ObjC1 && Lang.CPlusPlus  && it->first == CXXSystem)  ||
+        (Lang.ObjC1  && !Lang.CPlusPlus && it->first == ObjCSystem) ||
+        (Lang.ObjC1  && Lang.CPlusPlus  && it->first == ObjCXXSystem))
       SearchList.push_back(it->second);
   }
 
@@ -1147,17 +1127,6 @@ void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
                  E.IgnoreSysRoot);
   }
 
-  // Add entries from CPATH and friends.
-  Init.AddDelimitedPaths(HSOpts.EnvIncPath);
-  if (Lang.CPlusPlus && Lang.ObjC1)
-    Init.AddDelimitedPaths(HSOpts.ObjCXXEnvIncPath);
-  else if (Lang.CPlusPlus)
-    Init.AddDelimitedPaths(HSOpts.CXXEnvIncPath);
-  else if (Lang.ObjC1)
-    Init.AddDelimitedPaths(HSOpts.ObjCEnvIncPath);
-  else
-    Init.AddDelimitedPaths(HSOpts.CEnvIncPath);
-
   if (HSOpts.UseStandardIncludes)
     Init.AddDefaultSystemIncludePaths(Lang, Triple, HSOpts);
 
diff --git a/clang/test/Driver/cpath.c b/clang/test/Driver/cpath.c
new file mode 100644
index 00000000000..00ed879bc02
--- /dev/null
+++ b/clang/test/Driver/cpath.c
@@ -0,0 +1,20 @@
+// RUN: mkdir -p %T/test1 %T/test2
+
+// RUN: CPATH=%T/test1: %clang -x c -E -v %s 2>&1 | FileCheck %s -check-prefix=CPATH
+// CPATH: -I {{.*}}/test1 -I .
+// CPATH: search starts here
+// CPATH: test1
+
+// RUN: OBJC_INCLUDE_PATH=%T/test1  OBJCPLUS_INCLUDE_PATH=%T/test1  CPLUS_INCLUDE_PATH=%T/test1 C_INCLUDE_PATH=%T/test2 %clang -x c -E -v %s 2>&1 | FileCheck %s -check-prefix=C_INCLUDE_PATH
+// C_INCLUDE_PATH: -c-isystem {{.*}}/test2 -cxx-isystem {{.*}}/test1 -objc-isystem {{.*}}/test1 -objcxx-isystem {{.*}}/test1
+// C_INCLUDE_PATH: search starts here
+// C_INCLUDE_PATH-NOT: test1
+// C_INCLUDE_PATH: test2
+// C_INCLUDE_PATH-NOT: test1
+
+// RUN: OBJC_INCLUDE_PATH=%T/test1  OBJCPLUS_INCLUDE_PATH=%T/test2  CPLUS_INCLUDE_PATH=%T/test1 C_INCLUDE_PATH=%T/test1 %clang -x objective-c++ -E -v %s 2>&1 | FileCheck %s -check-prefix=OBJCPLUS_INCLUDE_PATH
+// OBJCPLUS_INCLUDE_PATH: -c-isystem {{.*}}/test1 -cxx-isystem {{.*}}/test1 -objc-isystem {{.*}}/test1 -objcxx-isystem {{.*}}/test2
+// OBJCPLUS_INCLUDE_PATH: search starts here
+// OBJCPLUS_INCLUDE_PATH-NOT: test1
+// OBJCPLUS_INCLUDE_PATH: test2
+// OBJCPLUS_INCLUDE_PATH-NOT: test1