Inconsistency in API specification for duplicate instrument names and spec-compliance-matrix

[srikanthccv]

API Spec says

When more than one Instrument of the same name is created for identical Meters, denoted duplicate instrument registration, the implementation MUST create a valid Instrument in every case. Here, "valid" means an instrument that is functional and can be expected to export data, despite potentially creating a semantic error in the data model.

When more than one distinct Instrument is registered with the same name for identical Meters, the implementation SHOULD emit a warning to the user informing them of duplicate registration conflict(s). The warning helps to avoid the semantic error state described in the OpenTelemetry Metrics data model when more than one Metric is written for a given instrument name and Meter identity by the same MeterProvider.

The spec-compliance-matrix has a row that requires returning error in the event of duplicate instrument name https://github.com/open-telemetry/opentelemetry-specification/blob/main/spec-compliance-matrix.md#metrics.

An error is returned when multiple instruments are registered under the same Meter using the same name.

I believe the compliance matrix is outdated and should reflect the API specification, If this is a correct assumption I can send a PR updating the matix.

[pichlermarc]

I think your assumption is correct. The wording seems to reflect the spec before #2317 landed.

[jsuereth]

Yep, this correct and please open a PR to update the matrix