tree 4abcbb7716ebf7b429329264f83d0f44869c6459
parent cebdbf3f293f5b0f3120c009c47da0ceadc113cb
author Ian Lance Taylor <iant@golang.org> 1518204747 -0800
committer Ian Lance Taylor <iant@golang.org> 1518463496 +0000

compiler: error on func declaration/definition

Long long long ago Go permitted writing
    func F()
in one file and writing
    func F() {}
in another file.  This was removed from the language, and that is now
considered to be a multiple definition error.  Gccgo never caught up
to that, and it has been permitting this invalid code for some time.

Stop permitting it, so that we give correct errors.  Since we've
supported it for a long time, the compiler uses it in a couple of
cases: it predeclares the hash/equal methods if it decides to create
them while compiling another function, and it predeclares main.main as
a mechanism for getting the right warning if a program uses the wrong
signature for main.  For simplicity, keep those existing uses.

This required a few minor changes in libgo which were relying,
unnecessarily, on the current behavior.

Change-Id: Ie8835aad9775ec6417cad766f42336adde60dc79
Reviewed-on: https://go-review.googlesource.com/93083
Reviewed-by: Than McIntosh <thanm@google.com>