Objective-C bazel target failed to build at 3.12.x

[stanley-cheung]

Environment: MacOS

At the 3.12.x branch, bazel build :protobuf_objc failed, but completed successfully at the 3.11.x branch.

At 3.12.x

stanleycheung@stanleycheung-macbookpro3:~/protobuf$ bazel build :protobuf_objc
Starting local Bazel server and connecting to it...
INFO: Analyzed target //:protobuf_objc (19 packages loaded, 238 targets configured).
INFO: Found 1 target...
ERROR: missing input file 'objectivec/google/protobuf/FieldMask.pbobjc.m', owner: '//:objectivec/google/protobuf/FieldMask.pbobjc.m'
ERROR: /Users/stanleycheung/protobuf/BUILD:969:1: //:protobuf_objc: missing input file '//:objectivec/google/protobuf/FieldMask.pbobjc.m'
ERROR: /Users/stanleycheung/protobuf/BUILD:969:1: C++ compilation of rule '//:protobuf_objc' failed: I/O exception during sandboxed execution: Running '/var/tmp/_bazel_stanleycheung/install/7afe40059062a3d2a6e3d7dae41ab49a/xcode-locator 11.3.1.11C505' failed.
Process terminated by signal 15
stdout: 
stderr: 
Target //:protobuf_objc failed to build
Use --verbose_failures to see the command lines of failed build steps.
ERROR: /Users/stanleycheung/protobuf/BUILD:969:1 1 input file(s) do not exist
INFO: Elapsed time: 5.224s, Critical Path: 0.09s
INFO: 0 processes.
FAILED: Build did NOT complete successfully

At 3.11.x

~/protobuf$ bazel build :protobuf_objc
Starting local Bazel server and connecting to it...
INFO: Analyzed target //:protobuf_objc (19 packages loaded, 238 targets configured).
INFO: Found 1 target...
Target //:protobuf_objc up-to-date:
  bazel-out/apl-darwin_x86_64-fastbuild/bin/libprotobuf_objc.a
INFO: Elapsed time: 8.173s, Critical Path: 2.48s
INFO: 25 processes: 25 darwin-sandbox.
INFO: Build completed successfully, 27 total actions

Could it be because of #7173? Is it because objectivec/GPBFieldMask.pbobjc.h is not part of hdrs in the :protobuf_objc BUILD rule? https://github.com/protocolbuffers/protobuf/blob/3.12.x/BUILD#L969

This patch seems to fix the issue:

diff --git a/BUILD b/BUILD
index 8ab4cb413..b32a1f161 100644
--- a/BUILD
+++ b/BUILD
@@ -969,6 +969,16 @@ alias(
 objc_library(
     name = "protobuf_objc",
     hdrs = [
+        "objectivec/GPBAny.pbobjc.h",
+        "objectivec/GPBApi.pbobjc.h",
+        "objectivec/GPBDuration.pbobjc.h",
+        "objectivec/GPBEmpty.pbobjc.h",
+        "objectivec/GPBFieldMask.pbobjc.h",
+        "objectivec/GPBSourceContext.pbobjc.h",
+        "objectivec/GPBStruct.pbobjc.h",
+        "objectivec/GPBTimestamp.pbobjc.h",
+        "objectivec/GPBType.pbobjc.h",
+        "objectivec/GPBWrappers.pbobjc.h",
         "objectivec/GPBArray.h",
         "objectivec/GPBBootstrap.h",
         "objectivec/GPBCodedInputStream.h",
@@ -1017,6 +1027,16 @@ objc_library(
         "objectivec",
     ],
     non_arc_srcs = [
+        "objectivec/GPBAny.pbobjc.m",
+        "objectivec/GPBApi.pbobjc.m",
+        "objectivec/GPBDuration.pbobjc.m",
+        "objectivec/GPBEmpty.pbobjc.m",
+        "objectivec/GPBFieldMask.pbobjc.m",
+        "objectivec/GPBSourceContext.pbobjc.m",
+        "objectivec/GPBStruct.pbobjc.m",
+        "objectivec/GPBTimestamp.pbobjc.m",
+        "objectivec/GPBType.pbobjc.m",
+        "objectivec/GPBWrappers.pbobjc.m",
         "objectivec/GPBArray.m",
         "objectivec/GPBCodedInputStream.m",
         "objectivec/GPBCodedOutputStream.m",
@@ -1031,16 +1051,6 @@ objc_library(
         "objectivec/GPBUtilities.m",
         "objectivec/GPBWellKnownTypes.m",
         "objectivec/GPBWireFormat.m",
-        "objectivec/google/protobuf/Any.pbobjc.m",
-        "objectivec/google/protobuf/Api.pbobjc.m",
-        "objectivec/google/protobuf/Duration.pbobjc.m",
-        "objectivec/google/protobuf/Empty.pbobjc.m",
-        "objectivec/google/protobuf/FieldMask.pbobjc.m",
-        "objectivec/google/protobuf/SourceContext.pbobjc.m",
-        "objectivec/google/protobuf/Struct.pbobjc.m",
-        "objectivec/google/protobuf/Timestamp.pbobjc.m",
-        "objectivec/google/protobuf/Type.pbobjc.m",
-        "objectivec/google/protobuf/Wrappers.pbobjc.m",
     ],
     visibility = ["//visibility:public"],
 )

[stanley-cheung]

Fixed by #7538