Go 1.15

[taowen]

@thockin @AllenX2018 https://lwn.net/SubscriberLink/820217/47ed80088c03b18d/

Due to Go's ability to inspect types at runtime (using the reflect package), Go binaries contain a significant amount of type information. CL 231397 by Cherry Zhang only includes a symbol's type information in the output if it's converted to an interface (only values converted to an interface can be used with reflection). This change reduces the size of a hello-world program by 7.2%.

https://github.com/modern-go/reflect2 is likely to be broken.

[AllenX2018]

I think TypeByName() and TypeByPackageName() in type_map.go are likely to be broken. But the other part I think they might work well. I'm not sure but I'll keep an eye on it.

[zhsj]

One test is failing with go1.15

    --- FAIL: Test_symmetric/map[test.stringKeyType]string (0.00s)

[liggitt]

I don't think this is actually related to a change in go1.15... it looks like that test is only enabled on go1.15:

go/type_tests/map_key_test.go

Lines 1 to 3 in 6821bec

	// +build go1.15
	// remove these tests temporarily until https://github.com/golang/go/issues/38105 and
	// https://github.com/golang/go/issues/38940 is fixed

and references an issue that was closed as working as designed:

golang/go#38940 (comment)

So I think that test should likely just be deleted (or actually, the test kept and json-iterator behavior made consistent with the stdlib)