[dev.typeparams] cmd/compile: allow inlining in instantiated functions

Change markType to scan generic types and methods, so that inlineable
functions inside generic functions/methods will be properly marked for
export, which means inlining inside instantiated functions will work
correctly.

Also, fix handling of closures for instantiated functions. Some code
needs to be adjusted, since instantiated functions/methods are compiled
as if in the package of the source generic function/type, rather than in
the local package. When we create the closure struct, we want to make
sure that the .F field has the same package as the other fields for the
closure variables. Also, we need to disable a check in tcCompLit() when
being done for an instantiated function, since fields of the closure
struct will be from the source package, not the local package.

Re-enabled part of the orderedmapsimp test that was disabled because of
these issues.

Change-Id: Ic4dba8917da0a36b17c0bdb69d6d6edfdf14104a
Reviewed-on: https://go-review.googlesource.com/c/go/+/324331
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

1 files changed, 13 insertions, 2 deletions

diff --git a/src/cmd/compile/internal/typecheck/expr.go b/src/cmd/compile/internal/typecheck/expr.go
index 24d141e8a2..30d864320f 100644
--- a/src/cmd/compile/internal/typecheck/expr.go
+++ b/src/cmd/compile/internal/typecheck/expr.go
@@ -311,8 +311,19 @@ func tcCompLit(n *ir.CompLitExpr) (res ir.Node) {
 
 				f := t.Field(i)
 				s := f.Sym
-				if s != nil && !types.IsExported(s.Name) && s.Pkg != types.LocalPkg {
-					base.Errorf("implicit assignment of unexported field '%s' in %v literal", s.Name, t)
+
+				// Do the test for assigning to unexported fields.
+				// But if this is an instantiated function, then
+				// the function has already been typechecked. In
+				// that case, don't do the test, since it can fail
+				// for the closure structs created in
+				// walkClosure(), because the instantiated
+				// function is compiled as if in the source
+				// package of the generic function.
+				if !(ir.CurFunc != nil && strings.Index(ir.CurFunc.Nname.Sym().Name, "[") >= 0) {
+					if s != nil && !types.IsExported(s.Name) && s.Pkg != types.LocalPkg {
+						base.Errorf("implicit assignment of unexported field '%s' in %v literal", s.Name, t)
+					}
 				}
 				// No pushtype allowed here. Must name fields for that.
 				n1 = AssignConv(n1, f.Type, "field value")