[expr.call]/1 seems to be the only place defining what is a "function call":
A function call is a postfix expression followed by parentheses containing a possibly empty, comma-separated list of initializer-clauses which constitute the arguments to the function.
The Index already includes "recursive function call" and "undefined function call". Lacking for the "function call" itself reveals imcompleteness.
[expr.call]/1 seems to be the only place defining what is a "function call":
The Index already includes "recursive function call" and "undefined function call". Lacking for the "function call" itself reveals imcompleteness.