Some fixes for the GYP subcommand of GN

This adds support for writing shorter paths if an output file is inside the output directory (previously we'd write "../../out/Debug/foo" when we could just write "foo"). Fixing this was necessary because we need to match GYP's input/output files exactly and GYP does this. I also fixed a buf with outputting root dirs not ending with a slash, and added an assertion that the output isn't system-absolute (since the code doesn't handle this yet).

The GYP integration didn't work due to slashes being different on Windows, so I convert them whem I read GYP's ninja file. I also deal with Windows lineendings.

Some buildfile fixes for GYP compatibility, and the previous patch had the wrong name for LASTCHANGE.

I changed the default to a non-component build since this is the GYP default. They both need to agree about this.

BUG=
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/25058007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226777 0039d316-1c4b-4281-b951-d872f2087c98

20 files changed, 240 insertions, 155 deletions

diff --git a/tools/gn/command_gyp.cc b/tools/gn/command_gyp.cc
index bb74a42..73e33e5 100644
--- a/tools/gn/command_gyp.cc
+++ b/tools/gn/command_gyp.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <algorithm>
 #include <fstream>
 
 #include "base/atomicops.h"
@@ -10,6 +11,7 @@
 #include "base/file_util.h"
 #include "base/process/launch.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "base/time/time.h"
 #include "tools/gn/build_settings.h"
 #include "tools/gn/commands.h"
@@ -70,6 +72,11 @@ bool SimpleNinjaParse(const std::string& data,
     std::string filename = data.substr(
         next_subninja + kSubninjaPrefixLen,
         line_end - next_subninja - kSubninjaPrefixLen);
+    TrimWhitespaceASCII(filename, TRIM_ALL, &filename);
+#if defined(OS_WIN)
+    // We always want our array to use forward slashes.
+    std::replace(filename.begin(), filename.end(), '\\', '/');
+#endif
     subninjas->insert(filename);
 
     next_subninja = line_end;
diff --git a/tools/gn/ninja_script_target_writer.cc b/tools/gn/ninja_script_target_writer.cc
index e74459c..4678ba0 100644
--- a/tools/gn/ninja_script_target_writer.cc
+++ b/tools/gn/ninja_script_target_writer.cc
@@ -75,14 +75,17 @@ std::string NinjaScriptTargetWriter::WriteRuleDefinition(
     rspfile += ".rsp";
 
     out_ << "rule " << custom_rule_name << std::endl;
-    out_ << "  command = $pythonpath gyp-win-tool action-wrapper $arch "
-         << rspfile << std::endl;
+    out_ << "  command = ";
+    path_output_.WriteFile(out_, settings_->build_settings()->python_path());
+    out_ << " gyp-win-tool action-wrapper $arch " << rspfile << std::endl;
     out_ << "  description = CUSTOM " << target_label << std::endl;
     out_ << "  restat = 1" << std::endl;
     out_ << "  rspfile = " << rspfile << std::endl;
 
     // The build command goes in the rsp file.
-    out_ << "  rspfile_content = $pythonpath ";
+    out_ << "  rspfile_content = ";
+    path_output_.WriteFile(out_, settings_->build_settings()->python_path());
+    out_ << " ";
     path_output_.WriteFile(out_, target_->script_values().script());
     args_template.WriteWithNinjaExpansions(out_);
     out_ << std::endl;
diff --git a/tools/gn/path_output.cc b/tools/gn/path_output.cc
index f67b3d4..4e71f9b 100644
--- a/tools/gn/path_output.cc
+++ b/tools/gn/path_output.cc
@@ -13,6 +13,10 @@ PathOutput::PathOutput(const SourceDir& current_dir,
                        EscapingMode escaping,
                        bool convert_slashes)
     : current_dir_(current_dir) {
+  CHECK(current_dir.is_source_absolute())
+      << "Currently this only supports writing to output directories inside "
+         "the source root. There needs to be some tweaks to PathOutput to make "
+         "doing this work correctly.";
   inverse_current_dir_ = InvertDir(current_dir_);
 
   options_.mode = escaping;
@@ -36,7 +40,10 @@ void PathOutput::WriteDir(std::ostream& out,
   if (dir.value() == "/") {
     // Writing system root is always a slash (this will normally only come up
     // on Posix systems).
-    out << "/";
+    if (slash_ending == DIR_NO_LAST_SLASH)
+      out << "/.";
+    else
+      out << "/";
   } else if (dir.value() == "//") {
     // Writing out the source root.
     if (slash_ending == DIR_NO_LAST_SLASH) {
@@ -54,6 +61,13 @@ void PathOutput::WriteDir(std::ostream& out,
       else
         out << inverse_current_dir_;
     }
+  } else if (dir == current_dir_) {
+    // Writing the same directory. This needs special handling here since
+    // we need to output something else other than the input.
+    if (slash_ending == DIR_INCLUDE_LAST_SLASH)
+      out << "./";
+    else
+      out << ".";
   } else if (slash_ending == DIR_INCLUDE_LAST_SLASH) {
     WritePathStr(out, dir.value());
   } else {
@@ -68,11 +82,15 @@ void PathOutput::WriteFile(std::ostream& out, const OutputFile& file) const {
   EscapeStringToStream(out, file.value(), options_);
 }
 
+void PathOutput::WriteFile(std::ostream& out,
+                           const base::FilePath& file) const {
+  // Assume native file paths are always absolute.
+  EscapeStringToStream(out, FilePathToUTF8(file), options_);
+}
+
 void PathOutput::WriteSourceRelativeString(
     std::ostream& out,
     const base::StringPiece& str) const {
-  // Input begins with two slashes, is relative to source root. Strip off
-  // the two slashes when cat-ing it.
   if (options_.mode == ESCAPE_SHELL) {
     // Shell escaping needs an intermediate string since it may end up
     // quoting the whole thing. On Windows, the slashes may already be
@@ -100,7 +118,13 @@ void PathOutput::WritePathStr(std::ostream& out,
                               const base::StringPiece& str) const {
   DCHECK(str.size() > 0 && str[0] == '/');
 
-  if (str.size() >= 2 && str[1] == '/') {
+  if (str.substr(0, current_dir_.value().size()) ==
+      base::StringPiece(current_dir_.value())) {
+    // The current dir is a prefix of the output file, so we can strip the
+    // prefix and write out the result.
+    EscapeStringToStream(out, str.substr(current_dir_.value().size()),
+                         options_);
+  } else if (str.size() >= 2 && str[1] == '/') {
     WriteSourceRelativeString(out, str.substr(2));
   } else {
     // Input begins with one slash, don't write the current directory since
diff --git a/tools/gn/path_output.h b/tools/gn/path_output.h
index 00bdbee..7372d47 100644
--- a/tools/gn/path_output.h
+++ b/tools/gn/path_output.h
@@ -16,6 +16,10 @@
 class OutputFile;
 class SourceFile;
 
+namespace base {
+class FilePath;
+}
+
 // Writes file names to streams assuming a certain input directory and
 // escaping rules. This gives us a central place for managing this state.
 class PathOutput {
@@ -53,6 +57,7 @@ class PathOutput {
 
   void WriteFile(std::ostream& out, const SourceFile& file) const;
   void WriteFile(std::ostream& out, const OutputFile& file) const;
+  void WriteFile(std::ostream& out, const base::FilePath& file) const;
   void WriteDir(std::ostream& out,
                 const SourceDir& dir,
                 DirSlashEnding slash_ending) const;
diff --git a/tools/gn/path_output_unittest.cc b/tools/gn/path_output_unittest.cc
index 5133b79..49f29c9 100644
--- a/tools/gn/path_output_unittest.cc
+++ b/tools/gn/path_output_unittest.cc
@@ -24,6 +24,14 @@ TEST(PathOutput, Basic) {
     writer.WriteFile(out, SourceFile("//foo.cc"));
     EXPECT_EQ("../../foo.cc", out.str());
   }
+  {
+    // Files in the output dir.
+    std::ostringstream out;
+    writer.WriteFile(out, SourceFile("//out/Debug/foo.cc"));
+    out << " ";
+    writer.WriteFile(out, SourceFile("//out/Debug/bar/baz.cc"));
+    EXPECT_EQ("foo.cc bar/baz.cc", out.str());
+  }
 #if defined(OS_WIN)
   {
     // System-absolute path.
@@ -170,9 +178,41 @@ TEST(PathOutput, WriteDir) {
     {
       std::ostringstream out;
       writer.WriteDir(out, SourceDir("/"),
-                      PathOutput::DIR_NO_LAST_SLASH);
+                      PathOutput::DIR_INCLUDE_LAST_SLASH);
       EXPECT_EQ("/", out.str());
     }
+    {
+      std::ostringstream out;
+      writer.WriteDir(out, SourceDir("/"),
+                      PathOutput::DIR_NO_LAST_SLASH);
+      EXPECT_EQ("/.", out.str());
+    }
+
+    // Output inside current dir.
+    {
+      std::ostringstream out;
+      writer.WriteDir(out, SourceDir("//out/Debug/"),
+                      PathOutput::DIR_INCLUDE_LAST_SLASH);
+      EXPECT_EQ("./", out.str());
+    }
+    {
+      std::ostringstream out;
+      writer.WriteDir(out, SourceDir("//out/Debug/"),
+                      PathOutput::DIR_NO_LAST_SLASH);
+      EXPECT_EQ(".", out.str());
+    }
+    {
+      std::ostringstream out;
+      writer.WriteDir(out, SourceDir("//out/Debug/foo/"),
+                      PathOutput::DIR_INCLUDE_LAST_SLASH);
+      EXPECT_EQ("foo/", out.str());
+    }
+    {
+      std::ostringstream out;
+      writer.WriteDir(out, SourceDir("//out/Debug/foo/"),
+                      PathOutput::DIR_NO_LAST_SLASH);
+      EXPECT_EQ("foo", out.str());
+    }
   }
   {
     // Empty build dir writer.
diff --git a/tools/gn/secondary/BUILD.gn b/tools/gn/secondary/BUILD.gn
index a99dbac..baf8664 100644
--- a/tools/gn/secondary/BUILD.gn
+++ b/tools/gn/secondary/BUILD.gn
@@ -9,11 +9,11 @@ group("root") {
     "//crypto",
     "//ipc",
     "//net",
-    "//net/third_party/nss/ssl",
+    "//net/third_party/nss:ssl",
     "//sdch",
     "//third_party/icu:icudata",
     "//third_party/leveldatabase",
-    "//third_party/zlib:chrome_zlib",
+    "//third_party/zlib",
     "//skia",
     "//tools/gn",
     "//url",
diff --git a/tools/gn/secondary/build/config/BUILDCONFIG.gn b/tools/gn/secondary/build/config/BUILDCONFIG.gn
index 10cb3b3..89ec6f7 100644
--- a/tools/gn/secondary/build/config/BUILDCONFIG.gn
+++ b/tools/gn/secondary/build/config/BUILDCONFIG.gn
@@ -20,7 +20,7 @@ declare_args() {
   # Set to build the Android version.
   is_android = false
   # Component build.
-  is_component_build = true
+  is_component_build = false
   # ChromeOS build.
   is_chromeos = false
   # Debug build.
diff --git a/tools/gn/secondary/chrome/BUILD.gn b/tools/gn/secondary/chrome/BUILD.gn
index 4ba0c43..d2e6795 100644
--- a/tools/gn/secondary/chrome/BUILD.gn
+++ b/tools/gn/secondary/chrome/BUILD.gn
@@ -195,7 +195,7 @@ custom("about_credits") {
   # is added or removed, it will change the result, but there is no way to
   # express this as a build dependency. We approximate this by depending on
   # the last change file to force an update whenever the code is updated.
-  source_prereqs = [ "//build/utils/LASTCHANGE" ]
+  source_prereqs = [ "//build/util/LASTCHANGE" ]
 
   hard_dep = true
 
diff --git a/tools/gn/secondary/crypto/BUILD.gn b/tools/gn/secondary/crypto/BUILD.gn
index 248b699..111c61b 100644
--- a/tools/gn/secondary/crypto/BUILD.gn
+++ b/tools/gn/secondary/crypto/BUILD.gn
@@ -4,8 +4,21 @@
 
 import("ssl/flags.gni")
 
+crypto_minimal_sources = [
+  "hmac.cc",
+  "hmac.h",
+  "hmac_win.cc",
+  "secure_util.cc",
+  "secure_util.h",
+  "symmetric_key.h",
+  "symmetric_key_win.cc",
+  "third_party/nss/chromium-sha256.h",
+  "third_party/nss/sha512.cc",
+]
+
 component("crypto") {
   external = true
+  output_name = "crcrypto"  # Avoid colliding with OpenSSL's libcrypto.
   sources = [
     "apple_keychain.h",
     "apple_keychain_ios.mm",
@@ -86,7 +99,6 @@ component("crypto") {
   ]
 
   deps = [
-    ":crypto_minimal",
     "//base",
     "//base/third_party/dynamic_annotations",
     "//crypto/ssl:metassl",
@@ -164,23 +176,18 @@ component("crypto") {
   }
 
   defines = [ "CRYPTO_IMPLEMENTATION" ]
+
+  # TODO(brettw) once GYP compat is no longer necessary, just move
+  # crypto_minimal_sources to the crypto_minimal target and include a
+  # dependency on it here.
+  sources += crypto_minimal_sources
 }
 
 # A minimal crypto subset for core features that small standalone targets can
 # use to reduce code size.
 static_library("crypto_minimal") {
   external = true
-  sources = [
-    "hmac.cc",
-    "hmac.h",
-    "hmac_win.cc",
-    "secure_util.cc",
-    "secure_util.h",
-    "symmetric_key.h",
-    "symmetric_key_win.cc",
-    "third_party/nss/chromium-sha256.h",
-    "third_party/nss/sha512.cc",
-  ]
+  sources = crypto_minimal_sources
 
   deps = [
     "//base",
diff --git a/tools/gn/secondary/crypto/ssl/BUILD.gn b/tools/gn/secondary/crypto/ssl/BUILD.gn
index a937a70..249ecc1 100644
--- a/tools/gn/secondary/crypto/ssl/BUILD.gn
+++ b/tools/gn/secondary/crypto/ssl/BUILD.gn
@@ -36,7 +36,7 @@ group("metassl") {
     assert(is_linux)
     direct_dependent_configs = ":system_ssl_config"
   } else {
-    deps = [ "//net/third_party/nss/ssl" ]
+    deps = [ "//net/third_party/nss:ssl" ]
   }
 
   forward_dependent_configs_from = deps
diff --git a/tools/gn/secondary/net/BUILD.gn b/tools/gn/secondary/net/BUILD.gn
index 95ac4bd..840a6de 100644
--- a/tools/gn/secondary/net/BUILD.gn
+++ b/tools/gn/secondary/net/BUILD.gn
@@ -1068,7 +1068,7 @@ component("net") {
     "//sdch",
     "//third_party/icu:icui18n",
     "//third_party/icu:icuuc",
-    "//third_party/zlib:chrome_zlib",
+    "//third_party/zlib",
     "//url",
   ]
 
@@ -1084,7 +1084,7 @@ component("net") {
       "udp/udp_socket_libevent.h",
     ]
     deps += [
-      #"//net/third_party/nss/ssl:crssl",
+      #"//net/third_party/nss:ssl",
       #"//third_party/nss:nspr",
       #"//third_party/nss:nss",
     ]
@@ -1104,7 +1104,7 @@ component("net") {
       "ssl/client_cert_store_impl_nss.cc",
     ]
     deps += [
-      #"//net/third_party/nss/ssl:crssl",
+      #"//net/third_party/nss:ssl",
       #"//third_party/nss:nspr",
       #"//third_party/nss:nss",
     ]
@@ -1207,6 +1207,7 @@ grit("net_resources") {
 }
 
 static_library("http_server") {
+  external = true
   sources = [
     "server/http_connection.cc",
     "server/http_connection.h",
diff --git a/tools/gn/secondary/net/third_party/nss/BUILD.gn b/tools/gn/secondary/net/third_party/nss/BUILD.gn
index 4e943c4..17a9bd1 100644
--- a/tools/gn/secondary/net/third_party/nss/BUILD.gn
+++ b/tools/gn/secondary/net/third_party/nss/BUILD.gn
@@ -1,3 +1,94 @@
 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
+
+config("crssl_config") {
+  includes = [
+    "//net/third_party/nss/ssl",
+  ]
+}
+
+# TODO(brettw) move this to net/third_party/nss/ssl once GYP backwards-compat
+# is no longer needed.
+component("ssl") {
+  external = true
+  # Not named "ssl" so the lib doesn't conflict with OpenSSL's libssl
+  output_name = "crssl"
+
+  sources = [
+    "ssl/authcert.c",
+    "ssl/cmpcert.c",
+    "ssl/derive.c",
+    "ssl/dtlscon.c",
+    #"ssl/os2_err.c",
+    #"ssl/os2_err.h",
+    "ssl/preenc.h",
+    "ssl/prelib.c",
+    "ssl/ssl.h",
+    "ssl/ssl3con.c",
+    "ssl/ssl3ecc.c",
+    "ssl/ssl3ext.c",
+    "ssl/ssl3gthr.c",
+    "ssl/ssl3prot.h",
+    "ssl/sslauth.c",
+    "ssl/sslcon.c",
+    "ssl/ssldef.c",
+    "ssl/sslenum.c",
+    "ssl/sslerr.c",
+    "ssl/sslerr.h",
+    "ssl/SSLerrs.h",
+    "ssl/sslerrstrs.c",
+    "ssl/sslgathr.c",
+    "ssl/sslimpl.h",
+    "ssl/sslinfo.c",
+    "ssl/sslinit.c",
+    "ssl/sslmutex.c",
+    "ssl/sslmutex.h",
+    "ssl/sslnonce.c",
+    "ssl/sslplatf.c",
+    "ssl/sslproto.h",
+    "ssl/sslreveal.c",
+    "ssl/sslsecur.c",
+    "ssl/sslsnce.c",
+    "ssl/sslsock.c",
+    "ssl/sslt.h",
+    "ssl/ssltrace.c",
+    "ssl/sslver.c",
+    "ssl/unix_err.c",
+    "ssl/unix_err.h",
+    "ssl/win32err.c",
+    "ssl/win32err.h",
+    "ssl/bodge/secitem_array.c",
+  ]
+
+  defines = [
+    "NO_PKCS11_BYPASS",
+    "NSS_ENABLE_ECC",
+    "USE_UTIL_DIRECTLY",
+  ]
+
+  configs -= "//build/config/compiler:chromium_code"
+  configs += "//build/config/compiler:no_chromium_code"
+
+  direct_dependent_configs = [ ":crssl_config" ]
+
+  if (is_win) {
+    sources -= [
+      "ssl/unix_err.c",
+      "ssl/unix_err.h",
+    ]
+  } else {
+    sources -= [
+      "ssl/win32err.c",
+      "ssl/win32err.h",
+    ]
+  }
+
+  if (is_linux) {
+    includes = [ "bodge" ]
+    configs += "//third_party/nss:nss_linux_config"
+  }
+  if (is_mac) {
+    sources -= "ssl/bodge/secitem_array.c"
+  }
+}
diff --git a/tools/gn/secondary/net/third_party/nss/ssl/BUILD.gn b/tools/gn/secondary/net/third_party/nss/ssl/BUILD.gn
deleted file mode 100644
index a06d85b..0000000
--- a/tools/gn/secondary/net/third_party/nss/ssl/BUILD.gn
+++ /dev/null
@@ -1,93 +0,0 @@
-# Copyright (c) 2013 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-config("crssl_config") {
-  includes = [
-    "//net/third_party/nss/ssl",
-  ]
-}
-
-component("ssl") {
-  external = true
-  # Not named "ssl" so the lib doesn't conflict with OpenSSL's libssl
-  output_name = "crssl"
-
-  sources = [
-    "authcert.c",
-    "cmpcert.c",
-    "derive.c",
-    "dtlscon.c",
-    #"os2_err.c",
-    #"os2_err.h",
-    "preenc.h",
-    "prelib.c",
-    "ssl.h",
-    "ssl3con.c",
-    "ssl3ecc.c",
-    "ssl3ext.c",
-    "ssl3gthr.c",
-    "ssl3prot.h",
-    "sslauth.c",
-    "sslcon.c",
-    "ssldef.c",
-    "sslenum.c",
-    "sslerr.c",
-    "sslerr.h",
-    "SSLerrs.h",
-    "sslerrstrs.c",
-    "sslgathr.c",
-    "sslimpl.h",
-    "sslinfo.c",
-    "sslinit.c",
-    "sslmutex.c",
-    "sslmutex.h",
-    "sslnonce.c",
-    "sslplatf.c",
-    "sslproto.h",
-    "sslreveal.c",
-    "sslsecur.c",
-    "sslsnce.c",
-    "sslsock.c",
-    "sslt.h",
-    "ssltrace.c",
-    "sslver.c",
-    "unix_err.c",
-    "unix_err.h",
-    "win32err.c",
-    "win32err.h",
-    "bodge/secitem_array.c",
-  ]
-
-  defines = [
-    "NO_PKCS11_BYPASS",
-    "NSS_ENABLE_ECC",
-    "USE_UTIL_DIRECTLY",
-  ]
-
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
-
-  direct_dependent_configs = [ ":crssl_config" ]
-
-  if (is_win) {
-    sources -= [
-      "unix_err.c",
-      "unix_err.h",
-    ]
-  } else {
-    sources -= [
-      "win32err.c",
-      "win32err.h",
-    ]
-  }
-
-  if (is_linux) {
-    includes = [ "bodge" ]
-    configs += "//third_party/nss:nss_linux_config"
-  }
-  if (is_mac) {
-    sources -= "bodge/secitem_array.c"
-  }
-
-}
diff --git a/tools/gn/secondary/sdch/BUILD.gn b/tools/gn/secondary/sdch/BUILD.gn
index 9396624..ea36d0a 100644
--- a/tools/gn/secondary/sdch/BUILD.gn
+++ b/tools/gn/secondary/sdch/BUILD.gn
@@ -52,5 +52,5 @@ static_library("sdch") {
     includes = [ "win" ]
   }
 
-  deps = [ "//third_party/zlib:chrome_zlib" ]
+  deps = [ "//third_party/zlib" ]
 }
diff --git a/tools/gn/secondary/skia/BUILD.gn b/tools/gn/secondary/skia/BUILD.gn
index 7f16db3..e09221c 100644
--- a/tools/gn/secondary/skia/BUILD.gn
+++ b/tools/gn/secondary/skia/BUILD.gn
@@ -63,33 +63,22 @@ config("skia_config") {
   }
 }
 
-component("skia") {
-  external = true
-
-  deps = [
-    ":skia_library",
-    ":skia_chrome",
-  ]
-
-  direct_dependent_configs = [ ":skia_config" ]
-
-  forward_dependent_configs_from = [
-    ":skia_library",
-    ":skia_chrome",
-  ]
-
-      #SKIA_IMPLEMENTATION=1
-  # ["clang==1", {
-  #   "xcode_settings": {
-  #     "WARNING_CFLAGS!": [
-  #       # Don"t warn about string->bool used in asserts.
-  #       "-Wstring-conversion",
-  #     ],
-  #   },
-  #   "cflags!": [
-  #     "-Wstring-conversion",
-  #   ],
-  # }],
+if (component_mode == "static_library") {
+  group("skia") {
+    deps = [
+      ":skia_library",
+      ":skia_chrome",
+    ]
+    forward_dependent_configs_from = deps
+  }
+} else {
+  shared_library("skia") {
+    deps = [
+      ":skia_library",
+      ":skia_chrome",
+      ":skia_common",
+    ]
+  }
 }
 
 config("skia_chrome_config") {
@@ -97,6 +86,7 @@ config("skia_chrome_config") {
 }
 
 static_library("skia_chrome") {
+  external = true
   sources = [
     "ext/analysis_canvas.cc",
     "ext/analysis_canvas.h",
@@ -406,6 +396,7 @@ skia_gpu_sources = [
 
 # TODO(brettw) finish this file.
 static_library("skia_library") {
+  external = true
   sources = [
     # this should likely be moved into src/utils in skia
     "//third_party/skia/src/core/SkFlate.cpp",
diff --git a/tools/gn/secondary/third_party/leveldatabase/BUILD.gn b/tools/gn/secondary/third_party/leveldatabase/BUILD.gn
index 8718a2d..dfab34b 100644
--- a/tools/gn/secondary/third_party/leveldatabase/BUILD.gn
+++ b/tools/gn/secondary/third_party/leveldatabase/BUILD.gn
@@ -20,6 +20,7 @@ config("leveldatabase_config") {
 }
 
 static_library("leveldatabase") {
+  external = true
   sources = [
     "env_chromium.cc",
     "env_chromium.h",
diff --git a/tools/gn/secondary/third_party/libxml/BUILD.gn b/tools/gn/secondary/third_party/libxml/BUILD.gn
index 2a7a3de..6f027c8 100644
--- a/tools/gn/secondary/third_party/libxml/BUILD.gn
+++ b/tools/gn/secondary/third_party/libxml/BUILD.gn
@@ -147,7 +147,7 @@ static_library("libxml2") {
 
   deps = [
     "//third_party/icu:icuuc",
-    "//third_party/zlib:chrome_zlib",
+    "//third_party/zlib",
   ]
 
   if (is_linux) {
diff --git a/tools/gn/secondary/third_party/snappy/BUILD.gn b/tools/gn/secondary/third_party/snappy/BUILD.gn
index 81bfc14..578b455 100644
--- a/tools/gn/secondary/third_party/snappy/BUILD.gn
+++ b/tools/gn/secondary/third_party/snappy/BUILD.gn
@@ -67,6 +67,6 @@ test("snappy_unittest") {
     ":snappy",
     "//base",
     "//testing:gtest",
-    "//third_party/zlib:chrome_zlib",
+    "//third_party/zlib",
   ]
 }
diff --git a/tools/gn/secondary/third_party/zlib/BUILD.gn b/tools/gn/secondary/third_party/zlib/BUILD.gn
index 749043c..99e963e 100644
--- a/tools/gn/secondary/third_party/zlib/BUILD.gn
+++ b/tools/gn/secondary/third_party/zlib/BUILD.gn
@@ -6,8 +6,14 @@ config("zlib_config") {
   includes = [ "." ]
 }
 
-static_library("chrome_zlib") {
+static_library("zlib") {
   external = true
+
+  if (!is_win) {
+    # Don't stomp on "libzlib" on other platforms.
+    output_name = "chrome_zlib"
+  }
+
   sources = [
     "adler32.c",
     "compress.c",
@@ -70,7 +76,7 @@ static_library("minizip") {
     cflags = [ "-Wno-parentheses-equality" ]
   }
 
-  deps = [ ":chrome_zlib" ]
+  deps = [ ":zlib" ]
 
   direct_dependent_configs = [ ":zlib_config" ]
 }
diff --git a/tools/gn/target.cc b/tools/gn/target.cc
index d51da55..487591f 100644
--- a/tools/gn/target.cc
+++ b/tools/gn/target.cc
@@ -191,8 +191,10 @@ void Target::PullDependentTargetInfo(std::set<const Config*>* unique_configs) {
       inherited_libraries_.insert(dep);
 
     // Inherited libraries and flags are inherited across static library
-    // boundaries.
-    if (dep->output_type() != SHARED_LIBRARY &&
+    // boundaries. For external targets, assume that the external_link_deps
+    // will take care of this.
+    if (!dep->external() &&
+        dep->output_type() != SHARED_LIBRARY &&
         dep->output_type() != EXECUTABLE) {
       const std::set<const Target*> inherited = dep->inherited_libraries();
       for (std::set<const Target*>::const_iterator i = inherited.begin();