MISRA-C Compliance

For safety-critical deployments (automotive ECUs, medical devices, avionics), Timber provides a MISRA-C:2012 compliant code emitter.

Generating MISRA-C Code

from timber.codegen.misra_c import MisraCEmitter, check_misra_compliance
from timber.frontends.auto_detect import parse_model

ir = parse_model("model.json")
emitter = MisraCEmitter(ir)
files = emitter.emit()

# Write files
for filename, content in files.items():
    with open(filename, "w") as f:
        f.write(content)

Compliance Checking

report = check_misra_compliance(files)
print(f"Violations: {report.violations}")
print(f"Warnings: {report.warnings}")
print(f"Compliant: {report.is_compliant}")

# Detailed rule results
for rule in report.rules:
    print(f"  Rule {rule.id}: {'PASS' if rule.passed else 'FAIL'} — {rule.description}")

Rules Checked

Rule	Description	Category
1.1	No compiler extensions	Required
10.1	Unsigned integer suffix enforcement	Required
14.4	Boolean conditions	Required
15.7	Else after if-else-if	Required
17.7	Return value usage	Required
20.7	Macro expansion	Required
21.1	No redefinition of standard identifiers	Required

Transformations Applied

The MISRA-C emitter wraps the standard C99 emitter and applies:

1. Unsigned suffix enforcement — all unsigned literals get U suffix
2. No compiler-specific extensions — pure ISO C
3. Standard identifier protection — no redefinition of reserved names
4. Compliance markers — generated headers include MISRA compliance declaration

Use Cases

• Automotive — ADAS systems, engine control, autonomous driving
• Medical devices — patient monitoring, diagnostic equipment
• Avionics — flight control systems, navigation
• Industrial — PLC controllers, safety-instrumented systems

Integration with Certification

The generated code, combined with the audit trail, provides documentation suitable for:

• ISO 26262 (automotive)
• IEC 62304 (medical software)
• DO-178C (avionics)