tree 92cf8f50a832ab1eb5b47b3f98d0aac572a2ba14
parent def26773749ba304ef17a9d8bf8a148a1dc29018
author Alan Donovan <adonovan@google.com> 1539721044 -0400
committer Alan Donovan <adonovan@google.com> 1539910785 +0000

go/analysis/passes/nilness: degenerate nil condition checker

This check uses the control-flow graph and SSA value graph to detect
problems such as:

	p := &v
	...
	if p != nil { // tautological condition
	}

and:

	if p == nil {
		print(*p) // nil dereference
	}

(It was originally developed within Google's Go analysis framework and
can now be published in a form useful to all analysis drivers.)

This CL also includes buildssa, an Analyzer that constructs SSA for
later analysis passes but does not report diagnostics or facts of its
own.

Change-Id: I27bc4eea10d71d958685a403234879112c21f433
Reviewed-on: https://go-review.googlesource.com/c/142698
Reviewed-by: Michael Matloob <matloob@golang.org>