[clang][Darwin] Refactor header search path logic into the driver

Summary:
This commit moves the logic for determining system, resource and C++
header search paths from CC1 to the driver. This refactor has already
been made for several platforms, but Darwin had been left behind.

This refactor tries to implement the previous search path logic with
perfect accuracy. In particular, the order of all include paths inside
CC1 and all paths that were skipped because nonexistent are conserved
after the refactor. This change was also tested against a code base
of significant size and revealed no problems.

Reviewers: jfb, arphaman

Subscribers: nemanjai, javed.absar, kbarton, christof, jkorous, dexonsmith, jsji, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61963

llvm-svn: 361278

1 files changed, 15 insertions, 51 deletions

diff --git a/clang/lib/Frontend/InitHeaderSearch.cpp b/clang/lib/Frontend/InitHeaderSearch.cpp
index d96fa81f73f..e6cd8235b01 100644
--- a/clang/lib/Frontend/InitHeaderSearch.cpp
+++ b/clang/lib/Frontend/InitHeaderSearch.cpp
@@ -210,6 +210,10 @@ void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
                                             const HeaderSearchOptions &HSOpts) {
   llvm::Triple::OSType os = triple.getOS();
 
+  if (triple.isOSDarwin()) {
+    llvm_unreachable("Include management is handled in the driver.");
+  }
+
   if (HSOpts.UseStandardSystemIncludes) {
     switch (os) {
     case llvm::Triple::CloudABI:
@@ -365,49 +369,7 @@ void InitHeaderSearch::AddDefaultCPlusPlusIncludePaths(
   // FIXME: temporary hack: hard-coded paths.
 
   if (triple.isOSDarwin()) {
-    bool IsBaseFound = true;
-    switch (triple.getArch()) {
-    default: break;
-
-    case llvm::Triple::ppc:
-    case llvm::Triple::ppc64:
-      IsBaseFound = AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
-                                                "powerpc-apple-darwin10", "",
-                                                "ppc64", triple);
-      IsBaseFound |= AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
-                                                 "powerpc-apple-darwin10", "",
-                                                 "ppc64", triple);
-      break;
-
-    case llvm::Triple::x86:
-    case llvm::Triple::x86_64:
-      IsBaseFound = AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
-                                                "i686-apple-darwin10", "",
-                                                "x86_64", triple);
-      IsBaseFound |= AddGnuCPlusPlusIncludePaths(
-          "/usr/include/c++/4.0.0", "i686-apple-darwin8", "", "", triple);
-      break;
-
-    case llvm::Triple::arm:
-    case llvm::Triple::thumb:
-      IsBaseFound = AddGnuCPlusPlusIncludePaths(
-          "/usr/include/c++/4.2.1", "arm-apple-darwin10", "v7", "", triple);
-      IsBaseFound |= AddGnuCPlusPlusIncludePaths(
-          "/usr/include/c++/4.2.1", "arm-apple-darwin10", "v6", "", triple);
-      break;
-
-    case llvm::Triple::aarch64:
-      IsBaseFound = AddGnuCPlusPlusIncludePaths(
-          "/usr/include/c++/4.2.1", "arm64-apple-darwin10", "", "", triple);
-      break;
-    }
-    // Warn when compiling pure C++ / Objective-C++ only.
-    if (!IsBaseFound &&
-        !(LangOpts.CUDA || LangOpts.OpenCL || LangOpts.RenderScript)) {
-      Headers.getDiags().Report(SourceLocation(),
-                                diag::warn_stdlibcxx_not_found);
-    }
-    return;
+    llvm_unreachable("Include management is handled in the driver.");
   }
 
   switch (os) {
@@ -464,6 +426,16 @@ void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
     break;
   }
 
+  // All header search logic is handled in the Driver for Darwin.
+  if (triple.isOSDarwin()) {
+    if (HSOpts.UseStandardSystemIncludes) {
+      // Add the default framework include paths on Darwin.
+      AddPath("/System/Library/Frameworks", System, true);
+      AddPath("/Library/Frameworks", System, true);
+    }
+    return;
+  }
+
   if (Lang.CPlusPlus && !Lang.AsmPreprocessor &&
       HSOpts.UseStandardCXXIncludes && HSOpts.UseStandardSystemIncludes) {
     if (HSOpts.UseLibcxx) {
@@ -474,14 +446,6 @@ void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
   }
 
   AddDefaultCIncludePaths(triple, HSOpts);
-
-  // Add the default framework include paths on Darwin.
-  if (HSOpts.UseStandardSystemIncludes) {
-    if (triple.isOSDarwin()) {
-      AddPath("/System/Library/Frameworks", System, true);
-      AddPath("/Library/Frameworks", System, true);
-    }
-  }
 }
 
 /// RemoveDuplicates - If there are duplicate directory entries in the specified