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Niels Lohmann 08d7fbb0a1 Read FILE* input with std::fgetc under MemorySanitizer (#5874)
With glibc and optimization, <stdio.h> turns getc_unlocked into an extern
inline function that reads the stdio buffer (fp->_IO_read_ptr) directly.
glibc, which is not instrumented, fills that buffer, so MemorySanitizer
treats the bytes as uninitialized and reports a false positive when the
parsers read from a FILE* (e.g., the fuzz harness FILE* leg, OSS-Fuzz
575915982). std::fgetc is an opaque call whose result MemorySanitizer treats
as initialized.

Select JSON_UNLOCKED_FILE_IO 0 when compiled with MemorySanitizer. This is a
regression from #5828 and not part of any release.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-21 10:22:50 +02:00
..
2025-04-11 10:41:14 +02:00
2025-04-11 10:41:14 +02:00
2026-10-11 08:21:51 +02:00

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