Driver: Change default use of "clang" compiler.

 - Don't default to using clang for C++ (use -ccc-clang-cxx to
   override).

 - Default to only using clang on i386 and x86_64 (use
   -ccc-clang-archs "" to override).

 - <rdar://problem/6712350> [driver] clang should not be used on
   powerpc by default
 - <rdar://problem/6705767> driver should default to -ccc-no-clang-cxx

I plan to add a warning that we are not using the clang compiler for
the given compilation so that users do not think clang is being used
in situations it isn't.

This change is motivated by the desire to be able to drop clang into a
build and have things "just work", even if it happens to get used to
compile C++ code or code for an architecture we don't support yet.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@67640 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Driver/Driver.h b/include/clang/Driver/Driver.h
index d1df4d87514c9a14adaec922ada75f1e52aef61b..5ba737379dafa638635c293e12eee7bf182e5fda 100644 (file)
--- a/include/clang/Driver/Driver.h
+++ b/include/clang/Driver/Driver.h
@@ -78,18 +78,18 @@ public:
   bool CCCPrintBindings : 1;
 
 private:
-  /// Don't use clang for any tasks.
-  bool CCCNoClang : 1;
+  /// Use the clang compiler where possible.
+  bool CCCUseClang : 1;
 
-  /// Don't use clang for handling C++ and Objective-C++ inputs.
-  bool CCCNoClangCXX : 1;
+  /// Use clang for handling C++ and Objective-C++ inputs.
+  bool CCCUseClangCXX : 1;
 
-  /// Don't use clang as a preprocessor (clang's preprocessor will
-  /// still be used where an integrated CPP would).
-  bool CCCNoClangCPP : 1;
+  /// Use clang as a preprocessor (clang's preprocessor will still be
+  /// used where an integrated CPP would).
+  bool CCCUseClangCPP : 1;
 
-  /// Only use clang for the given architectures. Only used when
-  /// non-empty.
+  /// Only use clang for the given architectures (only used when
+  /// non-empty).
   std::set<std::string> CCCClangArchs;
 
   /// Certain options suppress the 'no input files' warning.

diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index 1e10ac5c8f9d5266ac0c11ed2e06580da1beb18e..4411ac6fd20a3c48f543ba80de79ce4fbc55c71b 100644 (file)
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -43,9 +43,12 @@ Driver::Driver(const char *_Name, const char *_Dir,
     DefaultImageName(_DefaultImageName),
     Host(0),
     CCCIsCXX(false), CCCEcho(false), CCCPrintBindings(false),
-    CCCNoClang(false), CCCNoClangCXX(false), CCCNoClangCPP(false),
+    CCCUseClang(true), CCCUseClangCXX(false), CCCUseClangCPP(true),
     SuppressMissingInputWarning(false)
 {
+  // Only use clang on i386 and x86_64 by default.
+  CCCClangArchs.insert("i386");
+  CCCClangArchs.insert("x86_64");
 }
 
 Driver::~Driver() {
@@ -132,24 +135,27 @@ Compilation *Driver::BuildCompilation(int argc, const char **argv) {
     } else if (!strcmp(Opt, "echo")) {
       CCCEcho = true;
       
+    } else if (!strcmp(Opt, "clang-cxx")) {
+      CCCUseClangCXX = true;
     } else if (!strcmp(Opt, "no-clang")) {
-      CCCNoClang = true;
-    } else if (!strcmp(Opt, "no-clang-cxx")) {
-      CCCNoClangCXX = true;
+      CCCUseClang = false;
     } else if (!strcmp(Opt, "no-clang-cpp")) {
-      CCCNoClangCPP = true;
+      CCCUseClangCPP = false;
     } else if (!strcmp(Opt, "clang-archs")) {
       assert(Start+1 < End && "FIXME: -ccc- argument handling.");
       const char *Cur = *++Start;
     
+      CCCClangArchs.clear();
       for (;;) {
         const char *Next = strchr(Cur, ',');
 
         if (Next) {
-          CCCClangArchs.insert(std::string(Cur, Next));
+          if (Cur != Next)
+            CCCClangArchs.insert(std::string(Cur, Next));
           Cur = Next + 1;
         } else {
-          CCCClangArchs.insert(std::string(Cur));
+          if (*Cur != '\0')
+            CCCClangArchs.insert(std::string(Cur));
           break;
         }
       }
@@ -986,19 +992,19 @@ bool Driver::ShouldUseClangCompiler(const Compilation &C, const JobAction &JA,
                                     const std::string &ArchName) const {
   // Check if user requested no clang, or clang doesn't understand
   // this type (we only handle single inputs for now).
-  if (CCCNoClang || JA.size() != 1 || 
+  if (!CCCUseClang || JA.size() != 1 || 
       !types::isAcceptedByClang((*JA.begin())->getType()))
     return false;
 
-  // Otherwise make sure this is an action clang undertands.
+  // Otherwise make sure this is an action clang understands.
   if (isa<PreprocessJobAction>(JA)) {
-    if (CCCNoClangCPP)
+    if (!CCCUseClangCPP)
       return false;
   } else if (!isa<PrecompileJobAction>(JA) && !isa<CompileJobAction>(JA))
     return false;
 
-  // Avoid CXX if the user requested.
-  if (CCCNoClangCXX && types::isCXX((*JA.begin())->getType()))
+  // Use clang for C++?
+  if (!CCCUseClangCXX && types::isCXX((*JA.begin())->getType()))
     return false;
 
   // Finally, don't use clang if this isn't one of the user specified

diff --git a/test/Driver/bindings.c b/test/Driver/bindings.c
index 0e5623f0b81ca014d3e36b02d3a9db05ccccd596..9495eb2fba2575116d7c111f396ddd2c8a4b38f2 100644 (file)
--- a/test/Driver/bindings.c
+++ b/test/Driver/bindings.c
@@ -30,16 +30,23 @@
 // RUN: grep 'bind - "clang", inputs: \[".*bindings.c"\], output: (nothing)' %t &&
 // RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-print-bindings -ccc-no-clang -fsyntax-only %s 2> %t &&
 // RUN: grep 'bind - "gcc::Compile", inputs: \[".*bindings.c"\], output: (nothing)' %t &&
-// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-print-bindings -ccc-no-clang-cxx -fsyntax-only -x c++ %s 2> %t &&
+// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-print-bindings -fsyntax-only -x c++ %s 2> %t &&
 // RUN: grep 'bind - "gcc::Compile", inputs: \[".*bindings.c"\], output: (nothing)' %t &&
-// RUN: clang -ccc-print-bindings -ccc-no-clang-cpp -fsyntax-only -no-integrated-cpp -x c++ %s 2> %t &&
-// RUN: grep 'bind - "gcc::Preprocess", inputs: \[".*bindings.c"\], output: ".*\.ii"' %t &&
-// RUN: grep 'bind - "clang", inputs: \[".*\.ii"\], output: (nothing)' %t &&
-// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-host-triple i386-apple-darwin9 -ccc-print-bindings -ccc-clang-archs i386 %s -S -arch ppc 2> %t &&
+// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-print-bindings -ccc-clang-cxx -fsyntax-only -x c++ %s 2> %t &&
+// RUN: grep 'bind - "clang", inputs: \[".*bindings.c"\], output: (nothing)' %t &&
+// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-print-bindings -ccc-no-clang-cpp -fsyntax-only -no-integrated-cpp %s 2> %t &&
+// RUN: grep 'bind - "gcc::Preprocess", inputs: \[".*bindings.c"\], output: ".*\.i"' %t &&
+// RUN: grep 'bind - "clang", inputs: \[".*\.i"\], output: (nothing)' %t &&
+// RUN: clang -ccc-host-triple i386-apple-darwin9 -ccc-print-bindings -ccc-clang-archs i386 %s -S -arch ppc 2> %t &&
 // RUN: grep 'bind - "gcc::Compile", inputs: \[".*bindings.c"\], output: "bindings.s"' %t &&
-// RUN: clang -ccc-host-triple i386-unknown-unknown -ccc-host-triple i386-apple-darwin9 -ccc-print-bindings -ccc-clang-archs ppc %s -S -arch ppc 2> %t &&
+// RUN: clang -ccc-host-triple i386-apple-darwin9 -ccc-print-bindings -ccc-clang-archs ppc %s -S -arch ppc 2> %t &&
 // RUN: grep 'bind - "clang", inputs: \[".*bindings.c"\], output: "bindings.s"' %t &&
 
+// RUN: clang -ccc-host-triple powerpc-unknown-unknown -ccc-print-bindings -ccc-clang-archs "" %s -S 2> %t &&
+// RUN: grep 'bind - "clang", inputs: \[".*bindings.c"\], output: "bindings.s"' %t &&
+// RUN: clang -ccc-host-triple powerpc-unknown-unknown -ccc-print-bindings %s -S 2> %t &&
+// RUN: grep 'bind - "gcc::Compile", inputs: \[".*bindings.c"\], output: "bindings.s"' %t &&
+
 // Darwin bindings
 // RUN: clang -ccc-host-triple i386-apple-darwin9 -ccc-print-bindings %s 2> %t &&
 // RUN: grep 'bind - "clang", inputs: \[".*bindings.c"\], output: ".*\.s"' %t &&