Fix stack-overflow when nested Variants are used
Fix stack-overflow when nested Variants are used

See https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=4233

Credit to oss-fuzz

jpfr/open62541,open62541/open62541,JGrothoff/open62541,StalderT/open62541,jpfr/open62541,JGrothoff/open62541,JGrothoff/open62541,open62541/open62541,jpfr/open62541,open62541/open62541,JGrothoff/open62541,open62541/open62541,jpfr/open62541,StalderT/open62541,StalderT/open62541,StalderT/open62541