Remove name clashes of variables in macros #1628

Job	Run time
GCC build regression check (no tests)	1m 8s
Alpine Linux, musl, 32-bit (assert, x1.5)	14m 32s
macOS-M1, Clang (x3)	5m 32s
MinGW GCC (x0.5)	10m 35s
MSVC (x1)	9m 41s
Nemo.jl	19m 18s
Ubuntu Clang, BLAS and examples (x5)	3m 51s
Ubuntu GCC, Code Coverage (x10)	30m 43s
Ubuntu GCC with NTL (assert, x2)	8m 41s
	1h 44m 1s

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