bazel build --compilation_mode=debug (#6457)

.bazelrc

@@ -5,6 +5,7 @@ build --enable_platform_specific_config
 # On all platforms, provide: PYTHON3_BIN_PATH=python
 ###############################################################################
 build --action_env=PATH
+# For --compilation_mode=dbg, consider enabling checks in the standard library as well (below).
 build --compilation_mode=opt
 # This workaround is needed to prevent Bazel from compiling the same file twice (once PIC and once not).
 build:linux --force_pic
@@ -45,6 +46,14 @@ build:windows --color=yes
 build:windows --per_file_copt="-\\.(asm|S)$@-fansi-escape-codes"
 build:windows --per_file_copt="-\\.(asm|S)$@-fcolor-diagnostics"
 
+# Debug build flags. Uncomment in '-c dbg' builds to enable checks in the C++ standard library:
+#build:linux --cxxopt="-D_GLIBCXX_DEBUG=1"
+#build:linux --cxxopt="-D_GLIBCXX_DEBUG_PEDANTIC=1"
+#build:linux --cxxopt="-D_LIBCPP_DEBUG=1"
+#build:macos --cxxopt="-D_GLIBCXX_DEBUG=1"
+#build:macos --cxxopt="-D_GLIBCXX_DEBUG_PEDANTIC=1"
+#build:windows --cxxopt="-D_ITERATOR_DEBUG_LEVEL=2"
+
 # Thread sanitizer configuration:
 build:tsan --strip=never
 build:tsan --copt -fsanitize=thread

BUILD.bazel

@@ -7,7 +7,7 @@ load("@com_github_grpc_grpc//bazel:cc_grpc_library.bzl", "cc_grpc_library")
 load("@com_github_grpc_grpc//bazel:cython_library.bzl", "pyx_library")
 load("@rules_proto_grpc//python:defs.bzl", "python_grpc_compile")
 load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
-load("//bazel:ray.bzl", "COPTS")
+load("//bazel:ray.bzl", "COPTS", "PYX_COPTS", "PYX_SRCS")
 
 # === Begin of protobuf definitions ===
 
@@ -1598,7 +1598,8 @@ pyx_library(
     # We need to dlopen this lib with RTLD_GLOBAL to use ABI in this
     # shared lib, see python/ray/__init__.py.
     cc_kwargs = dict(
-        copts = COPTS,
+        srcs = PYX_SRCS,
+        copts = COPTS + PYX_COPTS,
         # see https://github.com/tensorflow/tensorflow/blob/r2.1/tensorflow/lite/BUILD#L444
         linkopts = select({
             "@bazel_tools//src/conditions:darwin": [
@@ -1636,7 +1637,8 @@ pyx_library(
         "python/ray/streaming/includes/*.pxi",
     ]),
     cc_kwargs = dict(
-        copts = COPTS,
+        srcs = PYX_SRCS,
+        copts = COPTS + PYX_COPTS,
     ),
     deps = [
         "//streaming:streaming_lib",

bazel/ray.bzl

@@ -13,6 +13,22 @@ COPTS = ["-DRAY_USE_GLOG"] + select({
     ],
 })
 
+PYX_COPTS = [] + select({
+    "@bazel_tools//src/conditions:windows": [
+        "/FI" + "src/shims/windows/python-nondebug.h",
+    ],
+    "//conditions:default": [
+    ],
+})
+
+PYX_SRCS = [] + select({
+    "@bazel_tools//src/conditions:windows": [
+        "src/shims/windows/python-nondebug.h",
+    ],
+    "//conditions:default": [
+    ],
+})
+
 def flatbuffer_py_library(name, srcs, outs, out_prefix, includes = [], include_paths = []):
     flatbuffer_library_public(
         name = name,

src/ray/util/logging.h

@@ -33,6 +33,16 @@
 enum { ERROR = 0 };
 #endif
 #endif
+
+#if defined(DEBUG) && DEBUG == 1
+// Bazel defines the DEBUG macro for historical reasons:
+// https://github.com/bazelbuild/bazel/issues/3513#issuecomment-323829248
+// Undefine the DEBUG macro to prevent conflicts with our usage below
+#undef DEBUG
+// Redefine DEBUG as itself to allow any '#ifdef DEBUG' to keep working regardless
+#define DEBUG DEBUG
+#endif
+
 namespace ray {
 
 enum class RayLogLevel { DEBUG = -1, INFO = 0, WARNING = 1, ERROR = 2, FATAL = 3 };

src/shims/windows/python-nondebug.h

@@ -0,0 +1,18 @@
+// This is to avoid depending on the debug version of the Python library on Windows,
+// which requires separate library files and linking.
+#if defined(_WIN32) && defined(_DEBUG)
+#ifdef Py_PYTHON_H
+#error Python.h should not have been included at this point.
+#endif
+// Ensure some headers included before messing with macro
+#include <io.h>
+#include <stdio.h>
+#ifdef Py_CONFIG_H
+#error pyconfig.h should not have been included at this point.
+#endif
+#include "patchlevel.h"
+#pragma push_macro("_DEBUG")
+#undef _DEBUG
+#include "pyconfig.h"
+#pragma pop_macro("_DEBUG")
+#endif