From 5e62be58be0e781c11fd735b5e130e77a2ecd7ad Mon Sep 17 00:00:00 2001
From: Xiao Peng <pengxiao@autra.tech>
Date: Fri, 4 Aug 2023 00:31:59 +0800
Subject: [PATCH] Add flag "--host_copts" to specify global host copts (#141)

Add cmd line options support to specify global host copts
---
 .bazelrc                            | 1 +
 README.md                           | 4 ++++
 cuda/BUILD.bazel                    | 5 +++++
 cuda/private/cuda_helper.bzl        | 2 +-
 cuda/private/rules/cuda_library.bzl | 1 +
 cuda/private/rules/cuda_objects.bzl | 1 +
 6 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/.bazelrc b/.bazelrc
index 474360a0..40a500d5 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -3,6 +3,7 @@ build --flag_alias=enable_cuda=//cuda:enable
 build --flag_alias=cuda_archs=//cuda:archs
 build --flag_alias=cuda_compiler=//cuda:compiler
 build --flag_alias=cuda_copts=//cuda:copts
+build --flag_alias=cuda_host_copts=//cuda:host_copts
 build --flag_alias=cuda_runtime=//cuda:runtime
 
 build --enable_cuda=True
diff --git a/README.md b/README.md
index 7d6d3c2c..ec906c50 100644
--- a/README.md
+++ b/README.md
@@ -77,6 +77,10 @@ bazel build --cuda_archs=compute_61:compute_61,sm_61
 
   Add the copts to all cuda compile actions.
 
+- `@rules_cuda//cuda:host_copts`
+
+  Add the copts to the host compiler.
+
 - `@rules_cuda//cuda:runtime`
 
   Set the default cudart to link, for example, `--@rules_cuda//cuda:runtime=@local_cuda//:cuda_runtime_static` link the static cuda runtime.
diff --git a/cuda/BUILD.bazel b/cuda/BUILD.bazel
index 2eba9a5c..59fe56b2 100644
--- a/cuda/BUILD.bazel
+++ b/cuda/BUILD.bazel
@@ -71,6 +71,11 @@ repeatable_string_flag(
     build_setting_default = "",
 )
 
+repeatable_string_flag(
+    name = "host_copts",
+    build_setting_default = "",
+)
+
 # Command line flag to specify the CUDA runtime. Use this target as CUDA
 # runtime dependency.
 #
diff --git a/cuda/private/cuda_helper.bzl b/cuda/private/cuda_helper.bzl
index f6d8a382..13cd9456 100644
--- a/cuda/private/cuda_helper.bzl
+++ b/cuda/private/cuda_helper.bzl
@@ -275,7 +275,7 @@ def _create_common(ctx):
         link_flags.extend([o for o in attr.linkopts if _check_opts(o)])
     host_defines = []
     host_local_defines = [i for i in attr.host_local_defines]
-    host_compile_flags = [i for i in attr.host_copts]
+    host_compile_flags = attr._default_host_copts[BuildSettingInfo].value + [i for i in attr.host_copts]
     host_link_flags = []
     if hasattr(attr, "host_linkopts"):
         host_link_flags.extend([i for i in attr.host_linkopts])
diff --git a/cuda/private/rules/cuda_library.bzl b/cuda/private/rules/cuda_library.bzl
index bdb40127..06e1f1a7 100644
--- a/cuda/private/rules/cuda_library.bzl
+++ b/cuda/private/rules/cuda_library.bzl
@@ -136,6 +136,7 @@ cuda_library = rule(
         "_builtin_deps": attr.label_list(default = ["//cuda:runtime"]),
         "_cc_toolchain": attr.label(default = "@bazel_tools//tools/cpp:current_cc_toolchain"),  # legacy behaviour
         "_default_cuda_copts": attr.label(default = "//cuda:copts"),
+        "_default_host_copts": attr.label(default = "//cuda:host_copts"),
         "_default_cuda_archs": attr.label(default = "//cuda:archs"),
     },
     fragments = ["cpp"],
diff --git a/cuda/private/rules/cuda_objects.bzl b/cuda/private/rules/cuda_objects.bzl
index b0fccdc3..2cc555ab 100644
--- a/cuda/private/rules/cuda_objects.bzl
+++ b/cuda/private/rules/cuda_objects.bzl
@@ -86,6 +86,7 @@ code and device link time optimization source files.""",
         "ptxasopts": attr.string_list(doc = "Add these flags to the ptxas command."),
         "_cc_toolchain": attr.label(default = "@bazel_tools//tools/cpp:current_cc_toolchain"),  # legacy behaviour
         "_default_cuda_copts": attr.label(default = "//cuda:copts"),
+        "_default_host_copts": attr.label(default = "//cuda:host_copts"),
         "_default_cuda_archs": attr.label(default = "//cuda:archs"),
     },
     fragments = ["cpp"],