ci: Add separate fuzz-only CI jobs with -DBUILD_FOR_FUZZING #31060

1. 
   dollarparity commented at 4:37 pm on October 8, 2024: none

   Certainly! Here is a title and description for your pull request that you can copy and paste:

   ---

   Title:

   ci: Add separate fuzz-only CI jobs with -DBUILD_FOR_FUZZING

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   Pull Request Description:

   ci: Add separate fuzz-only CI jobs with -DBUILD_FOR_FUZZING

   This pull request addresses [issue #31057](https://github.com/bitcoin/bitcoin/issues/31057) by updating the Continuous Integration (CI) workflow to disallow building the fuzz binary without -DBUILD_FOR_FUZZING and by adding separate fuzz-only CI jobs for macOS and Windows platforms.

   Changes:

   • Added new fuzz-only CI jobs:

     • macOS Fuzz Job (macos-fuzz):
       • Builds the fuzz binary with -DBUILD_FOR_FUZZING=ON.
       • Runs the fuzz tests after building.
     • Windows Fuzz Job (win64-fuzz):
       • Builds the fuzz binary with -DBUILD_FOR_FUZZING=ON.
       • Runs the fuzz tests after building.

   • Modified existing CI jobs:

     • macos-native-arm64:
       • Removed building of the fuzz binary without -DBUILD_FOR_FUZZING.
       • Ensured the job does not run fuzz tests.
     • win64-native:
       • Adjusted build steps to exclude the fuzz binary when -DBUILD_FOR_FUZZING is not set.
       • Ensured the job does not run fuzz tests.

   Rationale:

   Building the fuzz binary without -DBUILD_FOR_FUZZING results in a less effective binary for testing because:

   • It won’t crash on Assume statements.
   • It won’t bypass fuzz blockers with FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION.

   By creating separate fuzz-only CI jobs that use -DBUILD_FOR_FUZZING, we ensure:

   • The fuzz binary is correctly configured for testing.
   • Compile-time errors are caught early in the CI on all platforms.
   • Avoidance of workarounds like [PR #31028](https://github.com/bitcoin/bitcoin/pull/31028).

   Testing:

   • Validated that the new fuzz-only CI jobs run successfully and pass all fuzz tests.
   • Confirmed that the existing CI jobs continue to pass without building or running the fuzz binary.

   Notes:

   • This change complements updates made to disallow building the fuzz binary without -DBUILD_FOR_FUZZING in the build configuration.
   • Ensures consistency across all platforms in how fuzz binaries are built and tested.

   ---

   Fixes #31057

   CC: @dergoegge, @marcofleon, @maflcko

   ---

2. Update ci.yml

   Added separate fuzz-only CI jobs for macOS (macos-fuzz) and Windows (win64-fuzz) that build with -DBUILD_FOR_FUZZING=ON and run the fuzz tests.
   Adjusted existing CI jobs (macos-native-arm64 and win64-native) to exclude building the fuzz binary without -DBUILD_FOR_FUZZING.

   2dacfc723f
3. 
   DrahtBot commented at 4:37 pm on October 8, 2024: contributor

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4. DrahtBot added the label Tests on Oct 8, 2024
5. fanquake closed this on Oct 8, 2024

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6. dollarparity deleted the branch on Oct 8, 2024
7. bitcoin locked this on Oct 9, 2024

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dollarparity DrahtBot

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