cmd/compile: real and imag don't accept untyped non-complex constants as arguments

[griesemer]

package main
const _ = real(10.0)

=>

$ go build x.go
# command-line-arguments
./x.go:2: invalid argument 10 (type float64) for real

This seems inconsistent with complex(...) which accepts any untyped number as argument as long as it has no imaginary component or that component is zero. Similarly, real and float shouldn't really care about the nature of the untyped constant as long as it's a number.

gccgo accepts the above code w/o error.

Related issues: #11540, #11945.

[gopherbot]

CL https://golang.org/cl/12860 mentions this issue.

[ALTree]

This was fixed in 829adf5, so we can close this issue.