Empty compile_commands.json for building bitcoind

[SwJay]

Describe the bug Bear produces empty json for bitcoind. Actually, I've built it before using bear. Then I run make clean and build it again with bear, but it gives empty json again. Finally I start from git clone to get a clean workspace and build it with bear from beginning, but it still yields empty json file.

To Reproduce Steps to reproduce the behavior:

1. git clone git@github.com:bitcoin/bitcoin.git
2. install dependencies for bitcoind according to its doc.
3. build with bear

   bear ./autogen.sh
   bear ./configure
   bear make

Expected behavior non-empty json file.

Environment:

• OS name: Linux
• OS version: Ubuntu 18.04
• OS architecture: x86_64
• Bear version: 2.3.11
• Bear install method: apt install

Additional context

• Can you give us a reference to the project that you are running against this tool? https://github.com/bitcoin/bitcoin
• What build tools this project is using? GNU make
• What architecture you are trying to compile for? Compile on Linux
• Could you attach build logs? If you can re-run the command which failed (e.g. bear make) with extra verbose log switches (e.g. bear -vvvv make) and send the output of it, that would help a lot. The project is large and the log is way too long to paste.

Before you send...

• Have you read the README.md file or man bear? yes
• Have you looked what other open issues Bear has? yes
• Are you sure that the build works without Bear? yes

[rizsotto]

Thanks for the report @SwJay . Is there any way you could use the latest version of Bear? (The version you are using is about 4 years old.)

And either way (if you are using the new one or the old) I'll need some logs in order to help you. Could you attach the output of a verbose run? Or you can try to debug yourself, it's not that difficult. (It first intercepts the executed commands, then it try to recognize if it was a compiler call. Empty output means any of them is failing.)

[SwJay]

Thanks for your reply, and I'll try with the latest version first. If I failed to debug myself, I'll upload the log file and seek for help. Thanks!

[SwJay]

@rizsotto I've checked that the version 2.3.11 is the latest package on ubuntu 18.04. I built with bear [3.0.11] on macOS and it produces perfect json file. For the original issue, I reproduced the process and have log files here corresponding to three building steps.

[rizsotto]

I'm glad that you could use Bear to generate the desired JSON compilation database.

I'm closing this issue then. The newlocal errors are fixed since 2.3.11. :)