[PNaCl toolchain] Stop building and using custom libc++ for OSX hosts

toolchain_build/toolchain_build_pnacl.py

Index: toolchain_build/toolchain_build_pnacl.py
diff --git a/toolchain_build/toolchain_build_pnacl.py b/toolchain_build/toolchain_build_pnacl.py
index 985a520e4df8305c1792ee696d1c182a95a89ed9..218ddd9cddcb30dadfc2c3d33ea395aac5d65d17 100755
--- a/toolchain_build/toolchain_build_pnacl.py
+++ b/toolchain_build/toolchain_build_pnacl.py
@@ -272,18 +272,23 @@ def HostArchToolFlags(host, extra_cflags, opts):
     if TripleIsLinux(host) and not TripleIsX8664(host):
       # Chrome clang defaults to 64-bit builds, even when run on 32-bit Linux.
       extra_cc_flags += ['-m32']
-    if opts.gcc or host == 'le32-nacl':
-      result['CFLAGS']  += extra_cc_flags
-      result['CXXFLAGS'] += extra_cc_flags
-    else:
-      result['CFLAGS'] += extra_cc_flags
-      result['LDFLAGS'] += ['-L%(' + FlavoredName('abs_libcxx',
+    if not opts.gcc and host != 'le32-nacl':
+      # On mac and linux, use libc++ instead of libstdc++ (which is too old on
+      # Ubuntu Precise and any OSX to build LLVM)
+      result['CXXFLAGS'] += ['-stdlib=libc++']
+      if TripleIsLinux(host):
+        # Use our own libc++ on Linux.
+        # TODO(dschuff): Get the Chrome clang maintainers to build libc++ for
+        # Linux too and use that.
+        result['CXXFLAGS'] += ['-I%(' + FlavoredName('abs_libcxx', host, opts) +
+                               ')s/include/c++/v1']
+        result['LDFLAGS'] += ['-L%(' + FlavoredName('abs_libcxx',
                                                   host, opts) + ')s/lib']
-      result['CXXFLAGS'] += ([
-        '-stdlib=libc++',
-        '-I%(' + FlavoredName('abs_libcxx', host, opts) + ')s/include/c++/v1'] +
-        extra_cc_flags)
-      deps.append(FlavoredName('libcxx', host, opts))
+        deps.append(FlavoredName('libcxx', host, opts))
+
+    result['CFLAGS'] += extra_cc_flags
+    result['CXXFLAGS'] += extra_cc_flags
+
   return result, deps
 
 
@@ -572,14 +577,9 @@ def TestsuiteSources(GetGitSyncCmds):
 
 def CopyHostLibcxxForLLVMBuild(host, dest, options):
   """Copy libc++ to the working directory for build tools."""
-  if options.gcc:
-    return []
-  if TripleIsLinux(host):
-    libname = 'libc++.so.1'
-  elif TripleIsMac(host):
-    libname = 'libc++.1.dylib'
-  else:
+  if options.gcc or not TripleIsLinux(host):
     return []
+  libname = 'libc++.so.1'
   return [command.Mkdir(dest, parents=True),
           command.Copy('%(' +
                        FlavoredName('abs_libcxx', host, options) +')s/lib/' +
@@ -631,8 +631,8 @@ def HostLibs(host, options):
           ],
       },
     })
-  elif not options.gcc:
-    # Libc++ is only tested with the clang build
+  elif TripleIsLinux(host) and not options.gcc:
+    # Our Libc++ is only needed for Precise and only tested with clang.
     libcxx_host_arch_flags, libcxx_inputs = LibCxxHostArchFlags(host)
     libs.update({
         H('libcxx'): {
@@ -950,7 +950,7 @@ def TargetLibCompiler(host, options):
       },
   }
 
-  if TripleIsWindows(host) or not options.gcc:
+  if TripleIsWindows(host) or TripleIsLinux(host) and not options.gcc:
     host_lib = 'libdl' if TripleIsWindows(host) else H('libcxx')
     compiler['target_lib_compiler']['dependencies'].append(host_lib)
     compiler['target_lib_compiler']['commands'].append(
@@ -1198,7 +1198,7 @@ def GetUploadPackageTargets():
          'binutils_x86_%s' % legal_triple,
          'llvm_%s' % legal_triple,
          'driver_%s' % legal_triple])
-    if os_name != 'win':
+    if os_name == 'linux':
       host_packages[os_name].append('libcxx_%s' % legal_triple)
 
   # Unsandboxed target IRT libraries