Fixed the infamous `%E` scope bug #638

Job	Run time
coq	50s
mathcomp-classical	2m 48s
mathcomp	52s
mathcomp-analysis-single	2m 2s
mathcomp-reals	52s
mathcomp-experimental-reals	48s
mathcomp-reals-stdlib	53s
mathcomp-analysis	5m 45s
ssprove	0s
mathcomp-analysis-stdlib	0s
	14m 50s

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