Qualification
Formal Methods : Application to the Railway Domain

In its 2001 version, the CENELEC EN 50128 standard introduced a requirement for compiler qualification, without really indicating what was expected.

The 2011 version of CENELEC EN 50128 formally introduces the need to qualify tools (see § 6.7 of the standard). As with IEC 61508 and ISO 26262, three tool classes, T₁, T₂ , T₃, have been introduced:

• the T₁ class is dedicated to tools that have no impact on verification and no impact on the final executable;

• the T₂ class is dedicated to tools where a defect could distort verification or validation results. The T₂ class contains tools for coding rule verification, metrics measurement, static code analysis, test...