diff --git a/src/cmd/gc/dcl.c b/src/cmd/gc/dcl.c index 7bc9ce988ea..1c15e1eb6ef 100644 --- a/src/cmd/gc/dcl.c +++ b/src/cmd/gc/dcl.c @@ -151,16 +151,30 @@ void redeclare(Sym *s, char *where) { Strlit *pkgstr; + int line1, line2; if(s->lastlineno == 0) { pkgstr = s->origpkg ? s->origpkg->path : s->pkg->path; yyerror("%S redeclared %s\n" "\tprevious declaration during import \"%Z\"", s, where, pkgstr); - } else - yyerror("%S redeclared %s\n" + } else { + line1 = parserline(); + line2 = s->lastlineno; + + // When an import and a declaration collide in separate files, + // present the import as the "redeclared", because the declaration + // is visible where the import is, but not vice versa. + // See issue 4510. + if(s->def == N) { + line2 = line1; + line1 = s->lastlineno; + } + + yyerrorl(line1, "%S redeclared %s (%#N)\n" "\tprevious declaration at %L", - s, where, s->lastlineno); + s, where, s->def, line2); + } } static int vargen; diff --git a/test/fixedbugs/issue4510.dir/f1.go b/test/fixedbugs/issue4510.dir/f1.go new file mode 100644 index 00000000000..1e642e4ceef --- /dev/null +++ b/test/fixedbugs/issue4510.dir/f1.go @@ -0,0 +1,9 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package p + +import "fmt" // ERROR "fmt redeclared" + +var _ = fmt.Printf diff --git a/test/fixedbugs/issue4510.dir/f2.go b/test/fixedbugs/issue4510.dir/f2.go new file mode 100644 index 00000000000..895fc342ba1 --- /dev/null +++ b/test/fixedbugs/issue4510.dir/f2.go @@ -0,0 +1,7 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package p + +func fmt() {} diff --git a/test/fixedbugs/issue4510.go b/test/fixedbugs/issue4510.go new file mode 100644 index 00000000000..003f9e8e163 --- /dev/null +++ b/test/fixedbugs/issue4510.go @@ -0,0 +1,7 @@ +// errorcheckdir + +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ignored