From 394211bf88b88c25036429e99894fa7c60eaaace Mon Sep 17 00:00:00 2001 From: Yun Peng Date: Fri, 15 Sep 2017 15:59:14 +0200 Subject: Bazel now can build dynamic library from cc_library Working towards: https://github.com/bazelbuild/bazel/issues/3311 When building dynamic library on Windows, Bazel builds an import library and a DLL. Bazel provides a feature called windows_export_all_symbols, if this feature is enabled(and no_windows_export_all_symbols is not) for a cc_library, then Bazel parses object files of that cc_library to generate a DEF file that will be used during linking time to export symbols from DLL. This feature can be specified at crosstool, package, target and command line level. A few differences from Unix platforms: 1. We don't build the shared library on Windows by default, users have to specifiy --output_groups=dynamic_library for building dynamic libraries. This output group is also available on other platforms. 2. By default, cc_test is dynamically linked on Unix, but it will be statically linked on Windows by default. (meaning the default value of linkstatic in cc_test is 1 on Windows, and 0 on other platforms) 3. For global data symbols, __declspec(dllimport) must still be used in source files. Remaining issues: 1. Extensions for import library and DLL are not correct yet. 2. DLLs are not guaranteed to be available during runtime yet. 3. Diamond problem If a cc_library A is specified as linkstatic=0, then no dynamic library will be built for it, so if another cc_library B depends on it, A will be statically linked into B, and if a cc_binary C depends on B, A will also be statically linked into C and B will be dynamically linked to C. This is wrong because A is duplicated in both B and C. It is essentially a diamond problem describled in C++ Transitive Library. (https://docs.google.com/document/d/1-tv0_79zGyBoDmaP_pYWaBVUwHUteLpAs90_rUl-VY8/edit?usp=sharing) Hopefully, we can avoid this by using cc_shared_library rule in future. Change-Id: I23640d4caf8afe65d60b1522af6368536d7a8408 PiperOrigin-RevId: 168829958 --- src/create_embedded_tools.py | 1 + 1 file changed, 1 insertion(+) (limited to 'src/create_embedded_tools.py') diff --git a/src/create_embedded_tools.py b/src/create_embedded_tools.py index 699edd09f5..17d747fafc 100644 --- a/src/create_embedded_tools.py +++ b/src/create_embedded_tools.py @@ -45,6 +45,7 @@ output_paths = [ ('*Runner_deploy.jar', lambda x: 'tools/jdk/TestRunner_deploy.jar'), ('*singlejar', lambda x: 'tools/jdk/singlejar/singlejar'), ('*launcher.exe', lambda x: 'tools/launcher/launcher.exe'), + ('*def_parser.exe', lambda x: 'tools/def_parser/def_parser.exe'), ('*ijar.exe', lambda x: 'tools/jdk/ijar/ijar.exe'), ('*ijar', lambda x: 'tools/jdk/ijar/ijar'), ('*zipper.exe', lambda x: 'tools/zip/zipper/zipper.exe'), -- cgit v1.2.3