'samba_cv__CC_NEGATIVE_ENUM_VALUES' cv__ with two underscores instead of one source3/configure:13140:samba_cv__CC_NEGATIVE_ENUM_VALUES=no source3/configure.in:338: samba_cv_CC_NEGATIVE_ENUM_VALUES=yes,samba_cv__CC_NEGATIVE_ENUM_VALUES=no)])
Fixed with commit da2554117e2d9dc4bde7d47d6e81d5d572ca1d02