ctf-writer: avoid undefined behavior left shift

[babeltrace.git] / src / ctf-writer / stream.c

diff --git a/src/ctf-writer/stream.c b/src/ctf-writer/stream.c
index ccd7cc605bc797d01c3ab3df2fa8e644ed6aad27..41da4c88332e0a2538e88f09ecdd5ceb35e5bf00 100644 (file)
--- a/src/ctf-writer/stream.c
+++ b/src/ctf-writer/stream.c
@@ -480,7 +480,7 @@ static
 void update_clock_value(uint64_t *val, uint64_t new_val,
                unsigned int new_val_size)
 {
-       const uint64_t pow2 = 1ULL << new_val_size;
+       const uint64_t pow2 = new_val_size == 64 ? 0 : 1ULL << new_val_size;
        const uint64_t mask = pow2 - 1;
        uint64_t val_masked;