Reimplement whole archive on Windows

Use wrapper script to get object files if /WHOLEARCHIVE is not supported.

fix #1978
work towards #1918

--
Change-Id: I675311478e65a1e1f3fa963187a5a8da531150d3
Reviewed-on: https://bazel-review.googlesource.com/#/c/6833
MOS_MIGRATED_REVID=137151817

src/test/shell/bazel/bazel_windows_example_test.sh

@@ -60,6 +60,48 @@ function test_cpp() {
   assert_test_fails "//examples/cpp:hello-fail_test"
 }
 
+function test_cpp_alwayslink() {
+  mkdir -p cpp/main
+  cat >cpp/main/BUILD <<EOF
+cc_library(
+    name = "lib",
+    srcs = ["lib.cc"],
+    alwayslink = 1,
+)
+cc_library(
+    name = "main",
+    srcs = ["main.cc"],
+)
+cc_binary(
+    name = "bin",
+    deps = [":main", ":lib"],
+)
+EOF
+
+  cat >cpp/main/lib.cc <<EOF
+extern int global_variable;
+int init() {
+    ++global_variable;
+    return global_variable;
+}
+int x = init();
+int y = init();
+EOF
+
+  cat >cpp/main/main.cc <<EOF
+#include<stdio.h>
+int global_variable = 0;
+int main(void) {
+    printf("global : %d\n", global_variable);
+    return 0;
+}
+EOF
+  assert_build //cpp/main:bin
+  ./bazel-bin/cpp/main/bin >& $TEST_log \
+    || fail "//cpp/main:bin execution failed"
+  expect_log "global : 2"
+}
+
 function test_java() {
   local java_pkg=examples/java-native/src/main/java/com/example/myproject
 

tools/cpp/CROSSTOOL.tpl

@@ -293,6 +293,176 @@ toolchain {
     }
   }
 
+  action_config {
+     config_name: 'c++-link-executable'
+     action_name: 'c++-link-executable'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'linkstamps'
+     implies: 'output_execpath_flags'
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+  }
+
+  action_config {
+     config_name: 'c++-link-dynamic-library'
+     action_name: 'c++-link-dynamic-library'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'shared_flag'
+     implies: 'linkstamps'
+     implies: 'output_execpath_flags'
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+     implies: 'has_configured_linker_path'
+  }
+
+  action_config {
+     config_name: 'c++-link-static-library'
+     action_name: 'c++-link-static-library'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+  }
+
+  action_config {
+     config_name: 'c++-link-alwayslink-static-library'
+     action_name: 'c++-link-alwayslink-static-library'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+  }
+
+  # TODO(pcloudy): The following action_config is listed in MANDATORY_LINK_TARGET_TYPES.
+  # But do we really need them on Windows?
+  action_config {
+     config_name: 'c++-link-pic-static-library'
+     action_name: 'c++-link-pic-static-library'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+  }
+
+  action_config {
+     config_name: 'c++-link-alwayslink-pic-static-library'
+     action_name: 'c++-link-alwayslink-pic-static-library'
+     tool {
+         tool_path: 'wrapper/bin/msvc_link.bat'
+     }
+     implies: 'input_param_flags'
+     implies: 'global_whole_archive'
+  }
+
+  action_config {
+    config_name: 'c++-link-interface-dynamic-library'
+    action_name: 'c++-link-interface-dynamic-library'
+    tool {
+      tool_path: 'wrapper/bin/msvc_link.bat'
+    }
+  }
+
+  feature {
+    name: 'has_configured_linker_path'
+  }
+
+  feature {
+     name: 'shared_flag'
+     flag_set {
+         action: 'c++-link-dynamic-library'
+         flag_group {
+             flag: '/DLL'
+         }
+     }
+  }
+
+  feature {
+     name: 'linkstamps'
+     flag_set {
+         action: 'c++-link-executable'
+         action: 'c++-link-dynamic-library'
+         expand_if_all_available: 'linkstamp_paths'
+         flag_group {
+             flag: '%{linkstamp_paths}'
+         }
+     }
+  }
+
+  feature {
+     name: 'output_execpath_flags'
+     flag_set {
+         expand_if_all_available: 'output_execpath'
+         action: 'c++-link-executable'
+         action: 'c++-link-dynamic-library'
+         flag_group {
+             flag: '/OUT:%{output_execpath}'
+         }
+     }
+  }
+
+  feature {
+     name: 'input_param_flags'
+     flag_set {
+         expand_if_all_available: 'libopts'
+         action: 'c++-link-executable'
+         action: 'c++-link-dynamic-library'
+         action: 'c++-link-static-library'
+         action: 'c++-link-alwayslink-static-library'
+         action: 'c++-link-pic-static-library'
+         action: 'c++-link-alwayslink-pic-static-library'
+         flag_group {
+             flag: '%{libopts}'
+         }
+     }
+     flag_set {
+         expand_if_all_available: 'whole_archive_linker_params'
+         action: 'c++-link-executable'
+         action: 'c++-link-dynamic-library'
+         action: 'c++-link-static-library'
+         action: 'c++-link-alwayslink-static-library'
+         action: 'c++-link-pic-static-library'
+         action: 'c++-link-alwayslink-pic-static-library'
+         flag_group {
+            flag: '/WHOLEARCHIVE:%{whole_archive_linker_params}'
+         }
+     }
+     flag_set {
+         expand_if_all_available: 'linker_input_params'
+         action: 'c++-link-executable'
+         action: 'c++-link-dynamic-library'
+         action: 'c++-link-static-library'
+         action: 'c++-link-alwayslink-static-library'
+         action: 'c++-link-pic-static-library'
+         action: 'c++-link-alwayslink-pic-static-library'
+         flag_group {
+             flag: '%{linker_input_params}'
+         }
+     }
+  }
+
+  feature {
+   name: 'global_whole_archive'
+   flag_set {
+       expand_if_all_available: 'global_whole_archive'
+       action: 'c++-link-executable'
+       action: 'c++-link-dynamic-library'
+       action: 'c++-link-static-library'
+       action: 'c++-link-alwayslink-static-library'
+       action: 'c++-link-pic-static-library'
+       action: 'c++-link-alwayslink-pic-static-library'
+       flag_group {
+           flag: '/WHOLEARCHIVE'
+       }
+   }
+}
+
   compilation_mode_flags {
     mode: DBG
     compiler_flag: "/DDEBUG=1"

tools/cpp/cc_configure.bzl

@@ -428,6 +428,12 @@ def _find_env_vars(repository_ctx, vs_path):
   return env_map
 
 
+def _is_support_whole_archive(repository_ctx, vs_dir):
+  """Run MSVC linker alone to see if it supports /WHOLEARCHIVE."""
+  result = _execute(repository_ctx, [vs_dir + "/VC/BIN/amd64/link"])
+  return result.find("/WHOLEARCHIVE") != -1
+
+
 def _tpl(repository_ctx, tpl, substitutions={}, out=None):
   if not out:
     out = tpl
@@ -476,12 +482,19 @@ def _impl(repository_ctx):
     python_dir = python_binary[0:-10].replace("\\", "\\\\")
     include_paths = env["INCLUDE"] + (python_dir + "include")
     lib_paths = env["LIB"] + (python_dir + "libs")
+    lib_tool = vs_path + "/VC/bin/amd64/lib.exe"
+    if _is_support_whole_archive(repository_ctx, vs_path):
+      support_whole_archive = "True"
+    else:
+      support_whole_archive = "False"
     tmp_dir = _get_env_var(repository_ctx, "TMP", "C:\\Windows\\Temp")
     _tpl(repository_ctx, "wrapper/bin/pydir/msvc_tools.py", {
         "%{tmp}": tmp_dir.replace("\\", "\\\\"),
         "%{path}": env["PATH"],
         "%{include}": include_paths,
         "%{lib}": lib_paths,
+        "%{lib_tool}": lib_tool,
+        "%{support_whole_archive}": support_whole_archive
     })
 
     cxx_include_directories = []

tools/cpp/wrapper/bin/pydir/msvc_link.py

@@ -68,6 +68,9 @@ def Run(self, argv):
     # Build argument list.
     parser = msvc_tools.ArgParser(self, argv, LINKPATTERNS)
 
+    # Preprocessing arguments for linking whole archive libraries
+    parser.WholeArchivePreprocess()
+
     # Find the output file name.
     name = ''
     for arg in parser.options:

tools/cpp/wrapper/bin/pydir/msvc_tools.py.tpl

@@ -31,6 +31,7 @@ TMP_PATH = '%{tmp}'
 PATH = "%{path}"
 INCLUDE = "%{include}"
 LIB = "%{lib}"
+LIB_TOOL = "%{lib_tool}"
 
 class Error(Exception):
   """Base class for all script-specific errors."""
@@ -52,8 +53,38 @@ class ArgParser(object):
     self.deps_file = None
     self.output_file = None
     self.params_file = None
+    self.support_whole_archive = %{support_whole_archive}
+    self.need_global_whole_archive = None
     self._ParseArgs(argv)
 
+  def ReplaceLibrary(self, arg):
+    """Do the actual replacement if necessary."""
+    if arg == "/WHOLEARCHIVE":
+      return []
+    if arg.startswith("/OUT:") or os.path.splitext(arg)[1] not in ['.a', '.lo']:
+      return [arg]
+    if self.global_whole_archive or arg.startswith("/WHOLEARCHIVE:"):
+      if arg.startswith("/WHOLEARCHIVE:"):
+        arg = arg[len("/WHOLEARCHIVE:"):]
+      output = subprocess.check_output([LIB_TOOL, "/list", arg]).decode("utf-8")
+      object_files = []
+      for line in output.split("\n"):
+        line = line.strip()
+        if line.endswith(".o"):
+          object_files.append(line)
+      return object_files
+    return [arg]
+
+  def WholeArchivePreprocess(self):
+    """Replace library file with object files if /WHOLEARCHIVE is not supported."""
+    if self.support_whole_archive:
+      return
+    options = []
+    self.global_whole_archive = "/WHOLEARCHIVE" in self.options
+    for arg in self.options:
+      options.extend(self.ReplaceLibrary(arg))
+    self.options = options
+
   def _MatchOneArg(self, args):
     """Finds a pattern which matches the beginning elements of args.