ninja windows: support precompiled headers

pylib/gyp/generator/ninja.py

Index: pylib/gyp/generator/ninja.py
diff --git a/pylib/gyp/generator/ninja.py b/pylib/gyp/generator/ninja.py
index 19dcc1bb7fe788a0323c5de4946ee84350b21e59..e05aad6b84db3d225ecb02bdc46b571b65d6cc14 100644
--- a/pylib/gyp/generator/ninja.py
+++ b/pylib/gyp/generator/ninja.py
@@ -377,11 +377,16 @@ class NinjaWriter:
     link_deps = []
     sources = spec.get('sources', []) + extra_sources
     if sources:
+      pch = None
+      if self.flavor == 'mac':
+        pch = gyp.xcode_emulation.MacPrefixHeader(
+            self.xcode_settings, self.GypPathToNinja,
+            lambda path, lang: self.GypPathToUniqueOutput(path + '-' + lang))
+      elif self.flavor == 'win':
+        pch = gyp.msvs_emulation.PrecompiledHeader(
+            self.msvs_settings, config_name, self.GypPathToNinja)
       link_deps = self.WriteSources(
-          config_name, config, sources, compile_depends_stamp,
-          gyp.xcode_emulation.MacPrefixHeader(
-              self.xcode_settings, self.GypPathToNinja,
-              lambda path, lang: self.GypPathToUniqueOutput(path + '-' + lang)))
+          config_name, config, sources, compile_depends_stamp, pch)
       # Some actions/rules output 'sources' that are already object files.
       link_deps += [self.GypPathToNinja(f)
           for f in sources if f.endswith(self.obj_ext)]
@@ -681,6 +686,7 @@ class NinjaWriter:
       cflags_cc = self.msvs_settings.GetCflagsCC(config_name)
       extra_defines = self.msvs_settings.GetComputedDefines(config_name)
       self.WriteVariableList('pdbname', [self.name + '.pdb'])
+      self.WriteVariableList('pchprefix', [self.name])
     else:
       cflags = config.get('cflags', [])
       cflags_c = config.get('cflags_c', [])
@@ -701,7 +707,7 @@ class NinjaWriter:
         [QuoteShellArgument('-I' + self.GypPathToNinja(i), self.flavor)
          for i in include_dirs])
 
-    pch_commands = precompiled_header.GetGchBuildCommands()
+    pch_commands = precompiled_header.GetPchBuildCommands()
     if self.flavor == 'mac':
       self.WriteVariableList('cflags_pch_c',
                              [precompiled_header.GetInclude('c')])
@@ -748,7 +754,7 @@ class NinjaWriter:
       output = self.GypPathToUniqueOutput(filename + obj_ext)
       implicit = precompiled_header.GetObjDependencies([input], [output])
       self.ninja.build(output, command, input,
-                       implicit=[gch for _, _, gch in implicit],
+                       implicit=implicit,
                        order_only=predepends)
       outputs.append(output)
 
@@ -762,7 +768,7 @@ class NinjaWriter:
     if not pch_commands:
       return
 
-    for gch, lang_flag, lang, input in pch_commands:
+    for gch, lang_flag, lang, input, extra_variables in pch_commands:
       var_name = {
         'c': 'cflags_pch_c',
         'cc': 'cflags_pch_cc',
@@ -771,8 +777,9 @@ class NinjaWriter:
       }[lang]
 
       cmd = { 'c': 'cc', 'cc': 'cxx', 'm': 'objc', 'mm': 'objcxx', }.get(lang)
-      self.ninja.build(gch, cmd, input, variables=[(var_name, lang_flag)])
-
+      variables = [(var_name, lang_flag)]
+      variables += extra_variables
+      self.ninja.build(gch, cmd, input, variables=variables)
 
   def WriteLink(self, spec, config_name, config, link_deps):
     """Write out a link step. Fills out target.binary. """
@@ -1289,12 +1296,17 @@ def GenerateOutputForConfig(target_list, target_dicts, data, params,
   else:
     # TODO(scottmg): Requires fork of ninja for dependency and linking
     # support: https://github.com/sgraham/ninja
+    #
+    # Normally, we want to name the object file when we run compile step. This
+    # is done with /Fo. However, when compiling a precompiled header, the
+    # flag is /Fp, so override that in the pch compile step.
+    master_ninja.variable('outflag', '/Fo')
     master_ninja.rule(
       'cc',
       description='CC $out',
       command=('cmd /s /c "$cc /nologo /showIncludes '
                '@$out.rsp '
-               '$cflags_pch_c /c $in /Fo$out /Fd$pdbname '
+               '$cflags_pch_c /c $in $outflag$out $pchobj /Fd$pdbname '

[Nico, 2012/05/23 20:53:29]

Out of interest: Have you compared empty build times of this with having a
separate gch rule? (slightly fewer variable substitutions for compile rules.
probably not measurable, but if you happen to have measured it, I'd like to see
the numbers). If you haven't, don't bother.

[scottmg, 2012/05/24 20:34:39]

I didn't time it. I thought about doing it like that, but then the chance of
inconsistency seemed worse than a possible small difference in .ninja parse
time.

                '| ninja-deplist-helper -r . -q -f cl -o $out.dl"'),
       deplist='$out.dl',
       rspfile='$out.rsp',
@@ -1304,7 +1316,7 @@ def GenerateOutputForConfig(target_list, target_dicts, data, params,
       description='CXX $out',
       command=('cmd /s /c "$cxx /nologo /showIncludes '
                '@$out.rsp '
-               '$cflags_pch_cc /c $in /Fo$out /Fd$pdbname '
+               '$cflags_pch_cc /c $in $outflag$out $pchobj /Fd$pdbname '
                '| ninja-deplist-helper -r . -q -f cl -o $out.dl"'),
       deplist='$out.dl',
       rspfile='$out.rsp',