Fix the '-fuse-init-array' option to actually be an option.

Previously, this flag to CC1 was never exposed at the clang driver
layer, and if you happened to enable it (by being on Android or GCC 4.7
platform), you couldn't *disable* it, because there was no 'no' variant.
The whole thing was confusingly implemented.

Now, the target-specific flag processing gets the driver arg list, and
we use standard hasFlag with a default based on the GCC version and/or
Android platform. The user can still pass the 'no-' variant to forcibly
disable the flag, or pass the positive variant to clang itself to enable
the flag.

The test has also been substantially cleaned up and extended to cover
these use cases.

llvm-svn: 168473

4 files changed, 13 insertions, 6 deletions

diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index de8ed1d1c5e..8907b2ba97d 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -197,7 +197,8 @@ void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
   // Each toolchain should provide the appropriate include flags.
 }
 
-void ToolChain::addClangTargetOptions(ArgStringList &CC1Args) const {
+void ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
+                                      ArgStringList &CC1Args) const {
 }
 
 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
diff --git a/clang/lib/Driver/ToolChains.cpp b/clang/lib/Driver/ToolChains.cpp
index 94e30123293..118bf26d37c 100644
--- a/clang/lib/Driver/ToolChains.cpp
+++ b/clang/lib/Driver/ToolChains.cpp
@@ -2230,10 +2230,15 @@ Tool &Linux::SelectTool(const Compilation &C, const JobAction &JA,
   return *T;
 }
 
-void Linux::addClangTargetOptions(ArgStringList &CC1Args) const {
+void Linux::addClangTargetOptions(const ArgList &DriverArgs,
+                                  ArgStringList &CC1Args) const {
   const Generic_GCC::GCCVersion &V = GCCInstallation.getVersion();
-  if (V >= Generic_GCC::GCCVersion::Parse("4.7.0") ||
-      getTriple().getEnvironment() == llvm::Triple::Android)
+  bool UseInitArrayDefault
+    = V >= Generic_GCC::GCCVersion::Parse("4.7.0") ||
+      getTriple().getEnvironment() == llvm::Triple::Android;
+  if (DriverArgs.hasFlag(options::OPT_fuse_init_array,
+                         options::OPT_fno_use_init_array,
+                         UseInitArrayDefault))
     CC1Args.push_back("-fuse-init-array");
 }
 
diff --git a/clang/lib/Driver/ToolChains.h b/clang/lib/Driver/ToolChains.h
index 337ef200747..0b86b86b9ca 100644
--- a/clang/lib/Driver/ToolChains.h
+++ b/clang/lib/Driver/ToolChains.h
@@ -511,7 +511,8 @@ public:
 
   virtual void AddClangSystemIncludeArgs(const ArgList &DriverArgs,
                                          ArgStringList &CC1Args) const;
-  virtual void addClangTargetOptions(ArgStringList &CC1Args) const;
+  virtual void addClangTargetOptions(const ArgList &DriverArgs,
+                                     ArgStringList &CC1Args) const;
   virtual void AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
                                             ArgStringList &CC1Args) const;
 
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 5f483bd123f..32ae8d1b6e1 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2047,7 +2047,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                    AsynchronousUnwindTables))
     CmdArgs.push_back("-munwind-tables");
 
-  getToolChain().addClangTargetOptions(CmdArgs);
+  getToolChain().addClangTargetOptions(Args, CmdArgs);
 
   if (Arg *A = Args.getLastArg(options::OPT_flimited_precision_EQ)) {
     CmdArgs.push_back("-mlimit-float-precision");