Don't directly use buffer set in sbuff (CID #1634622) #9604

Job	Run time
pre-ci	8s
master-self-ubuntu24-linux-gcc-lean	7m 46s
master-self-ubuntu24-linux-gcc	8m 11s
master-self-ubuntu24-linux-gcc-O2-g3	8m 9s
master-self-ubuntu24-linux-gcc-ndebug	8m 23s
master-self-ubuntu24-linux-clang-lean	9m 12s
master-self-ubuntu24-linux-clang	10m 38s
master-self-ubuntu24-linux-clang-O2-g3	9m 54s
master-self-ubuntu24-linux-clang-ndebug	10m 22s
master-self-ubuntu24-linux-clang-altlibs	10m 8s
master-self-ubuntu24-linux-fuzzer	8m 11s
Merge into upstream	20s
	1h 31m 22s

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