In Go it is an error if the same name is defined in both the package
block (names defined anywhere in the package) and the file block (names
defined only in a single file, which can only happen via import
statements). The gccgo frontend was not diagnosing this error. This
patch fixes the problem. This required a tweak to one of the tests.
Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu.
Committed to mainline.
Ian
diff -r 9a016fbfe7b3 go/gogo.cc
--- a/go/gogo.cc Fri Dec 21 06:59:06 2012 -0800
+++ b/go/gogo.cc Fri Dec 21 14:19:44 2012 -0800
@@ -29,6 +29,7 @@
package_(NULL),
functions_(),
globals_(new Bindings(NULL)),
+ file_block_names_(),
imports_(),
imported_unsafe_(false),
packages_(),
@@ -1243,6 +1244,33 @@
else if (no->is_unknown())
no->unknown_value()->set_real_named_object(global_no);
}
+
+ // Give an error if any name is defined in both the package block
+ // and the file block. For example, this can happen if one file
+ // imports "fmt" and another file defines a global variable fmt.
+ for (Bindings::const_declarations_iterator p =
+ this->package_->bindings()->begin_declarations();
+ p != this->package_->bindings()->end_declarations();
+ ++p)
+ {
+ if (p->second->is_unknown()
+ && p->second->unknown_value()->real_named_object() == NULL)
+ {
+ // No point in warning about an undefined name, as we will
+ // get other errors later anyhow.
+ continue;
+ }
+ File_block_names::const_iterator pf =
+ this->file_block_names_.find(p->second->name());
+ if (pf != this->file_block_names_.end())
+ {
+ std::string n = p->second->message_name();
+ error_at(p->second->location(),
+ "%qs defined as both imported name and global name",
+ n.c_str());
+ inform(pf->second, "%qs imported here", n.c_str());
+ }
+ }
}
// Clear out names in file scope.
@@ -1250,7 +1278,7 @@
void
Gogo::clear_file_scope()
{
- this->package_->bindings()->clear_file_scope();
+ this->package_->bindings()->clear_file_scope(this);
// Warn about packages which were imported but not used.
bool quiet = saw_errors();
@@ -4855,7 +4883,7 @@
// Clear imports.
void
-Bindings::clear_file_scope()
+Bindings::clear_file_scope(Gogo* gogo)
{
Contour::iterator p = this->bindings_.begin();
while (p != this->bindings_.end())
@@ -4875,7 +4903,10 @@
if (keep)
++p;
else
- p = this->bindings_.erase(p);
+ {
+ gogo->add_file_block_name(p->second->name(), p->second->location());
+ p = this->bindings_.erase(p);
+ }
}
}
diff -r 9a016fbfe7b3 go/gogo.h
--- a/go/gogo.h Fri Dec 21 06:59:06 2012 -0800
+++ b/go/gogo.h Fri Dec 21 14:19:44 2012 -0800
@@ -377,6 +377,11 @@
void
add_named_object(Named_object*);
+ // Add an identifier to the list of names seen in the file block.
+ void
+ add_file_block_name(const std::string& name, Location location)
+ { this->file_block_names_[name] = location; }
+
// Mark all local variables in current bindings as used. This is
// used when there is a parse error to avoid useless errors.
void
@@ -678,6 +683,10 @@
// This is used for initialization dependency analysis.
typedef std::map<Variable*, Named_object*> Var_deps;
+ // Type used to map identifiers in the file block to the location
+ // where they were defined.
+ typedef Unordered_map(std::string, Location) File_block_names;
+
// Type used to queue writing a type specific function.
struct Specific_type_function
{
@@ -710,6 +719,8 @@
// The global binding contour. This includes the builtin functions
// and the package we are compiling.
Bindings* globals_;
+ // The list of names we have seen in the file block.
+ File_block_names file_block_names_;
// Mapping from import file names to packages.
Imports imports_;
// Whether the magic unsafe package was imported.
@@ -2265,7 +2276,7 @@
// Clear all names in file scope from the bindings.
void
- clear_file_scope();
+ clear_file_scope(Gogo*);
// Look up a name in this binding contour and in any enclosing
// binding contours. This returns NULL if the name is not found.
diff -r 9a016fbfe7b3 libgo/go/image/image_test.go
--- a/libgo/go/image/image_test.go Fri Dec 21 06:59:06 2012 -0800
+++ b/libgo/go/image/image_test.go Fri Dec 21 14:19:44 2012 -0800
@@ -10,7 +10,7 @@
"testing"
)
-type image interface {
+type timage interface {
Image
Opaque() bool
Set(int, int, color.Color)
@@ -24,7 +24,7 @@
}
func TestImage(t *testing.T) {
- testImage := []image{
+ testImage := []timage{
NewRGBA(Rect(0, 0, 10, 10)),
NewRGBA64(Rect(0, 0, 10, 10)),
NewNRGBA(Rect(0, 0, 10, 10)),
@@ -52,11 +52,11 @@
t.Errorf("%T: at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
continue
}
- if !m.SubImage(Rect(6, 3, 7, 4)).(image).Opaque() {
+ if !m.SubImage(Rect(6, 3, 7, 4)).(timage).Opaque() {
t.Errorf("%T: at (6, 3) was not opaque", m)
continue
}
- m = m.SubImage(Rect(3, 2, 9, 8)).(image)
+ m = m.SubImage(Rect(3, 2, 9, 8)).(timage)
if !Rect(3, 2, 9, 8).Eq(m.Bounds()) {
t.Errorf("%T: sub-image want bounds %v, got %v", m, Rect(3, 2, 9, 8), m.Bounds())
continue
@@ -97,7 +97,7 @@
continue
}
}
- testImage := []image{
+ testImage := []timage{
NewRGBA64(Rect(0, 0, 10, 10)),
NewNRGBA64(Rect(0, 0, 10, 10)),
NewAlpha16(Rect(0, 0, 10, 10)),
