52 lines
1.2 KiB
Go
52 lines
1.2 KiB
Go
package sa4012
|
|
|
|
import (
|
|
"honnef.co/go/tools/analysis/lint"
|
|
"honnef.co/go/tools/analysis/report"
|
|
"honnef.co/go/tools/go/ir"
|
|
"honnef.co/go/tools/go/ir/irutil"
|
|
"honnef.co/go/tools/internal/passes/buildir"
|
|
|
|
"golang.org/x/tools/go/analysis"
|
|
)
|
|
|
|
var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
|
|
Analyzer: &analysis.Analyzer{
|
|
Name: "SA4012",
|
|
Run: run,
|
|
Requires: []*analysis.Analyzer{buildir.Analyzer},
|
|
},
|
|
Doc: &lint.RawDocumentation{
|
|
Title: `Comparing a value against NaN even though no value is equal to NaN`,
|
|
Since: "2017.1",
|
|
Severity: lint.SeverityWarning,
|
|
MergeIf: lint.MergeIfAny,
|
|
},
|
|
})
|
|
|
|
var Analyzer = SCAnalyzer.Analyzer
|
|
|
|
func run(pass *analysis.Pass) (any, error) {
|
|
isNaN := func(v ir.Value) bool {
|
|
call, ok := v.(*ir.Call)
|
|
if !ok {
|
|
return false
|
|
}
|
|
return irutil.IsCallTo(call.Common(), "math.NaN")
|
|
}
|
|
for _, fn := range pass.ResultOf[buildir.Analyzer].(*buildir.IR).SrcFuncs {
|
|
for _, block := range fn.Blocks {
|
|
for _, ins := range block.Instrs {
|
|
ins, ok := ins.(*ir.BinOp)
|
|
if !ok {
|
|
continue
|
|
}
|
|
if isNaN(irutil.Flatten(ins.X)) || isNaN(irutil.Flatten(ins.Y)) {
|
|
report.Report(pass, ins, "no value is equal to NaN, not even NaN itself")
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return nil, nil
|
|
}
|