Restore functionality of --sysroot on FreeBSD after b18cb9c47

After b18cb9c47, clang would sometimes prefer the host C++ includes
(e.g. in /usr/include/c++/v1) before those specified via --sysroot.
While this behavior may be desirable on Linux, it is not so on FreeBSD,
where we make extensive use of --sysroot during the build of the base
system.  In that case, clang must *not* search outside the sysroot,
except for its own internal headers.

Add an override addLibCxxIncludePaths() to restore the old behavior,
which is to simply append /usr/include/c++/v1 to the specified sysroot.
While here, apply clang-format to the FreeBSD specific toolchain files.

Fixes PR44923.

(cherry picked from commit 62654cab7e654384ba503d6b62b1054cde19a553)

2 files changed, 15 insertions, 6 deletions

diff --git a/clang/lib/Driver/ToolChains/FreeBSD.cpp b/clang/lib/Driver/ToolChains/FreeBSD.cpp
index c5c6f530f48..6fb4ddd7f50 100644
--- a/clang/lib/Driver/ToolChains/FreeBSD.cpp
+++ b/clang/lib/Driver/ToolChains/FreeBSD.cpp
@@ -99,7 +99,8 @@ void freebsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   case llvm::Triple::sparcel:
   case llvm::Triple::sparcv9: {
     std::string CPU = getCPUName(Args, getToolChain().getTriple());
-    CmdArgs.push_back(sparc::getSparcAsmModeForCPU(CPU, getToolChain().getTriple()));
+    CmdArgs.push_back(
+        sparc::getSparcAsmModeForCPU(CPU, getToolChain().getTriple()));
     AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
     break;
   }
@@ -388,6 +389,12 @@ unsigned FreeBSD::GetDefaultDwarfVersion() const {
   return 4;
 }
 
+void FreeBSD::addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
+                                    llvm::opt::ArgStringList &CC1Args) const {
+  addSystemInclude(DriverArgs, CC1Args,
+                   getDriver().SysRoot + "/usr/include/c++/v1");
+}
+
 void FreeBSD::addLibStdCxxIncludePaths(
     const llvm::opt::ArgList &DriverArgs,
     llvm::opt::ArgStringList &CC1Args) const {
diff --git a/clang/lib/Driver/ToolChains/FreeBSD.h b/clang/lib/Driver/ToolChains/FreeBSD.h
index 84bdbfd9a31..7e13f48b716 100644
--- a/clang/lib/Driver/ToolChains/FreeBSD.h
+++ b/clang/lib/Driver/ToolChains/FreeBSD.h
@@ -59,16 +59,18 @@ public:
   bool IsObjCNonFragileABIDefault() const override { return true; }
 
   CXXStdlibType GetDefaultCXXStdlibType() const override;
-  void addLibStdCxxIncludePaths(
-      const llvm::opt::ArgList &DriverArgs,
-      llvm::opt::ArgStringList &CC1Args) const override;
+  void addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
+                             llvm::opt::ArgStringList &CC1Args) const override;
+  void
+  addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
+                           llvm::opt::ArgStringList &CC1Args) const override;
   void AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
                            llvm::opt::ArgStringList &CmdArgs) const override;
   void AddCudaIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                           llvm::opt::ArgStringList &CC1Args) const override;
 
-  llvm::ExceptionHandling GetExceptionModel(
-      const llvm::opt::ArgList &Args) const override;
+  llvm::ExceptionHandling
+  GetExceptionModel(const llvm::opt::ArgList &Args) const override;
   bool IsUnwindTablesDefault(const llvm::opt::ArgList &Args) const override;
   bool isPIEDefault() const override;
   SanitizerMask getSupportedSanitizers() const override;