[bazel] patch bindgen to recognise cc_library defines

Signed-off-by: Gary Guo <[email protected]>
Signed-off-by: Alex Jones <[email protected]>

Author: nbdd0121

third_party/rust/patches/rules_rust.bindgen_defines.patch

@@ -0,0 +1,50 @@
+commit 27500d1eaa0e8e0f8c53b8ff5a0b9772417cdb3b
+Author: Gary Guo <[email protected]>
+Date:   Fri Feb 14 15:18:37 2025 +0000
+
+    Propagate cc_library defines to clang
+
+diff --git a/extensions/bindgen/private/bindgen.bzl b/extensions/bindgen/private/bindgen.bzl
+index 6fa53571..1ebe104c 100644
+--- a/extensions/bindgen/private/bindgen.bzl
++++ b/extensions/bindgen/private/bindgen.bzl
+@@ -307,6 +307,10 @@ def _rust_bindgen_impl(ctx):
+             open_arg = True
+             continue
+
++    # Propagated defines should be made visible to clang
++    for define in ctx.attr.cc_lib[CcInfo].compilation_context.defines.to_list():
++        args.add("-D" + define)
++
+     _, _, linker_env = get_linker_and_args(ctx, "bin", cc_toolchain, feature_configuration, None)
+     env.update(**linker_env)
+
+diff --git a/extensions/bindgen/test/integration/simple/BUILD.bazel b/extensions/bindgen/test/integration/simple/BUILD.bazel
+index 0a1162b1..c52e8272 100644
+--- a/extensions/bindgen/test/integration/simple/BUILD.bazel
++++ b/extensions/bindgen/test/integration/simple/BUILD.bazel
+@@ -11,5 +11,6 @@ cc_library(
+     name = "simple",
+     srcs = ["simple.cc"],
+     hdrs = ["simple.h"],
++    defines = ["SIMPLE_DEFINE=1"],
+     visibility = ["//test/integration:__pkg__"],
+ )
+diff --git a/extensions/bindgen/test/integration/simple/simple.h b/extensions/bindgen/test/integration/simple/simple.h
+index a7ca3f43..d68c739a 100644
+--- a/extensions/bindgen/test/integration/simple/simple.h
++++ b/extensions/bindgen/test/integration/simple/simple.h
+@@ -9,8 +9,12 @@
+
+ #include <stdint.h>
+
++#ifdef SIMPLE_DEFINE
++
+ static const int64_t SIMPLE_VALUE = 42;
+
++#endif
++
+ EXTERN_C const int64_t simple_function();
+
+ static inline int64_t simple_static_function() { return 84; }
+

third_party/rust/rust.MODULE.bazel

@@ -21,6 +21,7 @@ single_version_override(
     module_name = "rules_rust_bindgen",
     patches = [
         "//third_party/rust/patches:rules_rust.bindgen_static_lib.patch",
+        "//third_party/rust/patches:rules_rust.bindgen_defines.patch",
     ],
     patch_strip = 3,
     version = "0.56.0",