E.1.3 Identifiers (G.3.3)
E.1.3.1 (6.1.2) The number of significant initial characters
(beyond 31) in an identifier without external linkage:
The first 1,023 characters are significant. Identifiers are case-sensitive.
(6.1.2) The number of significant initial characters
(beyond 6) in an identifier with external linkage:
The first 1,023 characters are significant. Identifiers are case-sensitive.