Add hint that genCppProto may need to be run

client/COMPILING.md

@@ -6,14 +6,14 @@ This was tested on Debian 12.5 and should also work on Raspberry Pi OS from 15.0
 * Install GRPC v1.63.0 or later like in the [official documentation](https://grpc.io/docs/languages/cpp/quickstart/) from source. This may take some time. If you are compiling on a Raspberry Pi, a Raspberry Pi 4 with at least 4 GB RAM is recommended.
 * Install libjsoncpp-dev and libpqxx-dev: `apt install libjsoncpp-dev libpqxx-dev`
 ## Compile
+**Hint:** If you changed the .proto file, you may need to run `./genCppProto.sh` before compiling.
 To compile the client run:
 ```
 mkdir -p cmake/build
 cd cmake/build
 cmake ../..
 make -j 3
 ```
-
 The binary `client` can be found in the cmake/build folder. This should be done on a Raspberry Pi if updates to the code were made. Otherwise, seting up cross compillation for arm64 should also be possible but is untested.
 
 **Note:** To run the mmclient locally, you also need to [install PostgreSQL](https://wiki.debian.org/PostgreSql) on your machine. For the setup see POSTGRES-SETUP.md. You may also want to look at deploy.sh
@@ -26,4 +26,4 @@ You can clone and switch the branch as follows:
 git clone https://github.com/nsg-ethz/pinpoint
 git checkout ci/addARMBuild
 ```
-then follow the same commands as in the official repo.
+then follow the same commands as in the official repo.