cmd/compile: have all or no parameter named in exported signatures
Binary export format only.
Make sure we don't accidentally export an unnamed parameter
in signatures which expect all named parameters; otherwise
we crash during import. Appears to happen for _ (blank)
parameter names, as observed in method signatures such as
the one at: x/tools/godoc/analysis/analysis.go:76.
Fixes #15470.
TBR=mdempsky
Change-Id: I1b1184bf08c4c09d8a46946539c4b8c341acdb84
Reviewed-on: https://go-review.googlesource.com/22543
Reviewed-by: Robert Griesemer <gri@golang.org>
diff --git a/src/cmd/compile/internal/gc/bexport.go b/src/cmd/compile/internal/gc/bexport.go
index 9c5d8bd..20c1aeb 100644
--- a/src/cmd/compile/internal/gc/bexport.go
+++ b/src/cmd/compile/internal/gc/bexport.go
@@ -819,19 +819,30 @@
}
p.typ(t)
if n > 0 {
- p.string(parName(q, numbered))
- // Because of (re-)exported inlined functions
- // the importpkg may not be the package to which this
- // function (and thus its parameter) belongs. We need to
- // supply the parameter package here. We need the package
- // when the function is inlined so we can properly resolve
- // the name.
- // TODO(gri) This is compiler-specific. Try using importpkg
- // here and then update the symbols if we find an inlined
- // body only. Otherwise, the parameter name is ignored and
- // the package doesn't matter. This would remove an int
- // (likely 1 byte) for each named parameter.
- p.pkg(q.Sym.Pkg)
+ if name := parName(q, numbered); name != "" {
+ p.string(name)
+ // Because of (re-)exported inlined functions
+ // the importpkg may not be the package to which this
+ // function (and thus its parameter) belongs. We need to
+ // supply the parameter package here. We need the package
+ // when the function is inlined so we can properly resolve
+ // the name.
+ // TODO(gri) This is compiler-specific. Try using importpkg
+ // here and then update the symbols if we find an inlined
+ // body only. Otherwise, the parameter name is ignored and
+ // the package doesn't matter. This would remove an int
+ // (likely 1 byte) for each named parameter.
+ p.pkg(q.Sym.Pkg)
+ } else {
+ // Sometimes we see an empty name even for n > 0.
+ // This appears to happen for interface methods
+ // with _ (blank) parameter names. Make sure we
+ // have a proper name and package so we don't crash
+ // during import (see also issue #15470).
+ // TODO(gri) review parameter encoding
+ p.string("_")
+ p.pkg(localpkg)
+ }
}
// TODO(gri) This is compiler-specific (escape info).
// Move into compiler-specific section eventually?
