fix #277, fix #260: fix crash

Fix crash because of parallel access to ssa.Program

Author: jirfag

.gitignore

@@ -3,3 +3,4 @@
 /dist/
 /.idea/
 /test/path
+/golangci-lint

Makefile

@@ -1,10 +1,14 @@
 test:
-	go install ./cmd/...
-	GL_TEST_RUN=1 golangci-lint run -v
-	GL_TEST_RUN=1 golangci-lint run --fast --no-config -v
-	GL_TEST_RUN=1 golangci-lint run --no-config -v
+	go build -o golangci-lint ./cmd/golangci-lint
+	GL_TEST_RUN=1 ./golangci-lint run -v
+	GL_TEST_RUN=1 ./golangci-lint run --fast --no-config -v
+	GL_TEST_RUN=1 ./golangci-lint run --no-config -v
 	GL_TEST_RUN=1 go test -v ./...
 
+test_race:
+	go build -race -o golangci-lint ./cmd/golangci-lint
+	GL_TEST_RUN=1 ./golangci-lint run -v --deadline=5m
+
 test_linters:
 	GL_TEST_RUN=1 go test -v ./test -count 1 -run TestSourcesFromTestdataWithIssuesDir/$T
 

pkg/golinters/megacheck.go

@@ -106,7 +106,7 @@ func (m Megacheck) Run(ctx context.Context, lintCtx *linter.Context) ([]result.I
 		return nil, nil
 	}
 
-	issues := runMegacheck(lintCtx.Program, lintCtx.SSAProgram, lintCtx.LoaderConfig,
+	issues := runMegacheck(lintCtx.Program, lintCtx.MegacheckSSAProgram, lintCtx.LoaderConfig,
 		m.StaticcheckEnabled, m.GosimpleEnabled, m.UnusedEnabled, lintCtx.Settings().Unused.CheckExported)
 	if len(issues) == 0 {
 		return nil, nil

pkg/lint/linter/context.go

@@ -17,7 +17,8 @@ type Context struct {
 	LoaderConfig *loader.Config  // deprecated, don't use for new linters
 	Program      *loader.Program // deprecated, use Packages for new linters
 
-	SSAProgram *ssa.Program
+	SSAProgram          *ssa.Program // for unparam and interfacer: they don't change it
+	MegacheckSSAProgram *ssa.Program // for megacheck: it modifies ssa program
 
 	Cfg      *config.Config
 	ASTCache *astcache.Cache

pkg/lint/load.go

@@ -126,13 +126,16 @@ func (cl ContextLoader) makeFakeLoaderProgram(pkgs []*packages.Package) *loader.
 	}
 }
 
-func (cl ContextLoader) buildSSAProgram(pkgs []*packages.Package) *ssa.Program {
+func (cl ContextLoader) buildSSAProgram(pkgs []*packages.Package, name string) *ssa.Program {
 	startedAt := time.Now()
+	var pkgsBuiltDuration time.Duration
 	defer func() {
-		cl.log.Infof("SSA repr building took %s", time.Since(startedAt))
+		cl.log.Infof("SSA %srepr building timing: packages building %s, total %s",
+			name, pkgsBuiltDuration, time.Since(startedAt))
 	}()
 
 	ssaProg, _ := ssautil.Packages(pkgs, ssa.GlobalDebug)
+	pkgsBuiltDuration = time.Since(startedAt)
 	ssaProg.Build()
 	return ssaProg
 }
@@ -300,24 +303,10 @@ func (cl ContextLoader) Load(ctx context.Context, linters []linter.Config) (*lin
 		prog = cl.makeFakeLoaderProgram(pkgs)
 	}
 
-	var ssaProg *ssa.Program
+	var ssaProg, megacheckSSAProg *ssa.Program
 	if loadMode == packages.LoadAllSyntax {
-		ssaProg = cl.buildSSAProgram(pkgs)
-		for _, pkginfo := range prog.InitialPackages() {
-			if pkginfo == nil {
-				cl.log.Infof("Pkginfo is nil")
-				continue
-			}
-			if pkginfo.Pkg == nil {
-				cl.log.Infof("Pkg %#v: types package is nil", *pkginfo)
-				continue
-			}
-			ssaPkg := ssaProg.Package(pkginfo.Pkg)
-			if ssaPkg == nil {
-				cl.log.Infof("Pkg %#v: ssaPkg is nil: %#v", *pkginfo, *pkginfo.Pkg)
-				continue
-			}
-		}
+		ssaProg = cl.buildSSAProgram(pkgs, "")
+		megacheckSSAProg = cl.buildSSAProgram(pkgs, "for megacheck ")
 	}
 
 	astLog := cl.log.Child("astcache")
@@ -327,9 +316,10 @@ func (cl ContextLoader) Load(ctx context.Context, linters []linter.Config) (*lin
 	}
 
 	ret := &linter.Context{
-		Packages:   pkgs,
-		Program:    prog,
-		SSAProgram: ssaProg,
+		Packages:            pkgs,
+		Program:             prog,
+		SSAProgram:          ssaProg,
+		MegacheckSSAProgram: megacheckSSAProg,
 		LoaderConfig: &loader.Config{
 			Cwd:   "",  // used by depguard and fallbacked to os.Getcwd
 			Build: nil, // used by depguard and megacheck and fallbacked to build.Default