fix dimassoc unit-test for DEBUGGING #4683

Job	Run time
linux-cmake	2m 0s
linux (CFLAGS="-O1 -fno-omit-frame-pointer -fsanitize=address -fno-var-tracking" --disable-bindin...	14m 53s
linux (CC="clang")	6m 49s
linux (--enable-release)	32m 33s
macOS	11m 14s
linux (--enable-gcov --disable-bindings --disable-docs CFLAGS="-O0 -g")	5m 17s
linux (--disable-write --disable-docs)	9m 45s
mingw	30m 3s
linux (CFLAGS="-O2 -m32" --disable-bindings --disable-docs)	7m 34s
mingw-cmake	3m 11s
linux (CFLAGS="-O2 -fno-omit-frame-pointer -fsanitize=undefined -fno-var-tracking" --disable-bind...	31m 20s
mips32-big-endian	26m 21s
ppc64-big-endian	7m 47s
vs2019	5m 14s
vs2019-ninja	5m 7s
	3h 19m 8s

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