golang/go

cmd/cgo: map sized integer types to C equivalents

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#29,878 opened on Jan 22, 2019

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Description

(Removing the template since this is an enhancement proposal)

The type mappings at https://golang.org/cmd/cgo/#hdr-Go_references_to_C don't state which Go types the sized C integer types int8_t etc. are mapped to. In C, these types have the same requirements as the corresponding Go types: they are not allowed to have padding bits and have to use two's complement representation, see https://en.cppreference.com/w/c/types/integer. Therefore, these types are guaranteed to have the same domain and representation as the corresponding Go types. So I propose to always represent these types with each other and formally document that fact. It would reduce the need for casts and would make it more obvious that there's no chance of data loss.

Contributor guide

Research direction
Investigate the current cgo type mappings for sized integer types (int8 t, etc.) and propose a change to automatically map them to corresponding Go types, updating documentation accordingly.
Tech stack
go
Domain
backend
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Mostly clear
Prerequisites
None
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60