Special-case paths that appear in libs by not prefixing them with -l.

tools/gn/config_values_generator.cc

 // 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.
 
 #include "tools/gn/config_values_generator.h"
 
 #include "base/strings/string_util.h"
 #include "tools/gn/config_values.h"
 #include "tools/gn/scope.h"
 #include "tools/gn/settings.h"
@@ skipping 61 matching lines @@
   FILL_STRING_CONFIG_VALUE(asmflags)
   FILL_STRING_CONFIG_VALUE(cflags)
   FILL_STRING_CONFIG_VALUE(cflags_c)
   FILL_STRING_CONFIG_VALUE(cflags_cc)
   FILL_STRING_CONFIG_VALUE(cflags_objc)
   FILL_STRING_CONFIG_VALUE(cflags_objcc)
   FILL_STRING_CONFIG_VALUE(defines)
   FILL_DIR_CONFIG_VALUE(   include_dirs)
   FILL_STRING_CONFIG_VALUE(ldflags)
   FILL_DIR_CONFIG_VALUE(   lib_dirs)
-  FILL_STRING_CONFIG_VALUE(libs)
 
 #undef FILL_STRING_CONFIG_VALUE
 #undef FILL_DIR_CONFIG_VALUE
 
+  // Libs
+  const Value* libs_value = scope_->GetValue("libs", true);
+  if (libs_value) {
+    std::vector<LibFile> result;
+    ExtractListOfLibs(scope_->settings()->build_settings(), *libs_value,
+                      input_dir_, &result, err_);
+    config_values_->libs().swap(result);
+  }
+
   // Precompiled headers.
   const Value* precompiled_header_value =
       scope_->GetValue(variables::kPrecompiledHeader, true);
   if (precompiled_header_value) {
     if (!precompiled_header_value->VerifyTypeIs(Value::STRING, err_))
       return;
 
     // Check for common errors. This is a string and not a file.
     const std::string& pch_string = precompiled_header_value->string_value();
     if (base::StartsWith(pch_string, "//", base::CompareCase::SENSITIVE)) {
@@ skipping 10 matching lines @@
       scope_->GetValue(variables::kPrecompiledSource, true);
   if (precompiled_source_value) {
     config_values_->set_precompiled_source(
         input_dir_.ResolveRelativeFile(
             *precompiled_source_value, err_,
             scope_->settings()->build_settings()->root_path_utf8()));
     if (err_->has_error())
       return;
   }
 }