fuzzing: make ossfuzz.sh resilient to individual compile failures#1
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fuzzing: make ossfuzz.sh resilient to individual compile failures#1tc-agent wants to merge 1 commit into
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Clang 22 (used by OSS-Fuzz since ~Dec 2025) has a compiler bug that segfaults when instantiating templates for msgpack_roundtrip_string.cpp. The set -e in ossfuzz.sh caused the entire build to abort on this single failure, leaving all other working fuzzers unbuilt. Remove -e from set -eux and wrap each compile in an if/else block so that a single compilation failure is logged as a warning but does not abort the build. Add a final check that exits non-zero only if zero fuzzers were built, preserving the invariant that a completely broken build is still an error. This unblocks the OSS-Fuzz build, which has been failing since 2025-12-18 (last successful build ID: 51ac6718-86c6-44f0-93c3-700557ee939c).
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Summary
The OSS-Fuzz build for glaze has been broken since 2025-12-18 (last successful build) because Clang 22 (adopted by OSS-Fuzz around that time) segfaults when compiling
fuzzing/msgpack_roundtrip_string.cpp.The crash occurs during template instantiation of the msgpack write path for
std::string— specifically inTransformNestedNameSpecifierLocduring C++23 concept constraint evaluation. This is a compiler bug, not a code bug.Root Cause
ossfuzz.shusesset -eux, which causes the entire build to abort when a single compilation fails. All 18 other fuzz harnesses compile fine on Clang 22 and were being silently skipped due to this one crash.Fix
Remove
-efromset -euxand wrap each compilation in anif/elseblock so that individual failures are logged as warnings but do not abort the build. A final check exits non-zero only if zero fuzzers were built, preserving the invariant that a completely broken build is still an error.This unblocks OSS-Fuzz and restores fuzzing coverage for the 18 harnesses that compile correctly. Fuzz Introspector reports 53.81% (3,772/7,010 lines) from the last successful build in December 2025.