Cannot find libstdc++-6.dll with MinGW

[jesseschalken]

Issue Description

When protoc is compiled with MinGW, it has a dependency on libstdc++-6.dll which is found (typically) in C:\msys64\mingw64\bin.

The only way an executable can find this DLL is by having C:\msys64\mingw64\bin in it's PATH, but rules_proto_grpc runs protoc without passing use_default_shell_env = True which causes it to run with only the workspace root in the PATH, preventing libstdc++-6.dll from being found.

Issue can be reprocuced by running bazel build --compiler=mingw-gcc //... in the example/c/c_proto_compile directory on Windows, with MinGW installed.

Log Output

INFO: Invocation ID: 9cab3575-b92f-442b-afd9-374be79aecb9
DEBUG: Rule 'com_google_absl' indicated that a canonical reproducible form can be obtained by modifying arguments sha256 = "316cb2947e0a39a9359071991c2632418a466c78f3d27a7efe8d30dd384a0d06"
DEBUG: Repository com_google_absl instantiated at:
  C:/projects/rules_proto_grpc/example/c/c_proto_compile/WORKSPACE:24:9: in <toplevel>
  C:/users/blah/_bazel_blah/ir7hhvo4/external/upb/bazel/workspace_deps.bzl:5:10: in upb_deps
  C:/users/blah/_bazel_blah/ir7hhvo4/external/bazel_tools/tools/build_defs/repo/utils.bzl:233:18: in maybe
Repository rule http_archive defined at:
  C:/users/blah/_bazel_blah/ir7hhvo4/external/bazel_tools/tools/build_defs/repo/http.bzl:364:31: in <toplevel>
INFO: Analyzed 3 targets (2 packages loaded, 4 targets configured).
INFO: Found 3 targets...
ERROR: C:/projects/rules_proto_grpc/example/c/c_proto_compile/BUILD.bazel:13:16: Compiling protoc outputs for upb_plugin plugin on target //:thing_c_proto failed: (Exit 127): bash.exe failed: error executing command C:\msys64\usr\bin\bash.exe -c mkdir -p 'bazel-out/x64_windows-fastbuild/bin/_rpg_premerge_thing_c_proto' && bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe $@  ... (remaining 4 arguments skipped)
C:/users/blah/_bazel_blah/ir7hhvo4/execroot/__main__/bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe: error while loading shared libraries: libstdc++-6.dll: cannot open shared object file: No such file or directory
ERROR: C:/projects/rules_proto_grpc/example/c/c_proto_compile/BUILD.bazel:3:16: Compiling protoc outputs for upb_plugin plugin on target //:person_c_proto failed: (Exit 127): bash.exe failed: error executing command C:\msys64\usr\bin\bash.exe -c mkdir -p 'bazel-out/x64_windows-fastbuild/bin/_rpg_premerge_person_c_proto' && bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe $@  ... (remaining 4 arguments skipped)
C:/users/blah/_bazel_blah/ir7hhvo4/execroot/__main__/bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe: error while loading shared libraries: libstdc++-6.dll: cannot open shared object file: No such file or directory
ERROR: C:/projects/rules_proto_grpc/example/c/c_proto_compile/BUILD.bazel:8:16: Compiling protoc outputs for upb_plugin plugin on target //:place_c_proto failed: (Exit 127): bash.exe failed: error executing command C:\msys64\usr\bin\bash.exe -c mkdir -p 'bazel-out/x64_windows-fastbuild/bin/_rpg_premerge_place_c_proto' && bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe $@  ... (remaining 4 arguments skipped)
C:/users/blah/_bazel_blah/ir7hhvo4/execroot/__main__/bazel-out/x64_windows-opt-exec-2B5CBBC6/bin/external/com_google_protobuf/protoc.exe: error while loading shared libraries: libstdc++-6.dll: cannot open shared object file: No such file or directory
INFO: Elapsed time: 1.480s, Critical Path: 0.46s
INFO: 4 processes: 4 internal.
FAILED: Build did NOT complete successfully

rules_proto_grpc Version

master

Bazel Version

5.0.0

OS

Windows 10

Link to Demo Repo

https://github.com/rules-proto-grpc/rules_proto_grpc/tree/master/example/c/c_proto_compile

WORKSPACE Content

No response

BUILD Content

No response

Proto Content

No response

Any Other Content

No response