[metadata]
id = "FLP36-C"
type = "rule"
category = "FLP"
number = 36
title = "Preserve precision when converting integral values to floating-point type"
description = """
Narrower arithmetic types can be cast to wider types without any effect on the
magnitude of numeric values. However, whereas integer types represent exact
values, floating-point types have limited precision. The C Standard, 6.3.1.4
paragraph 3 [ISO/IEC 9899:2024], states
Conversion from integral types to floating-point types without sufficient
precision can lead to loss of precision (loss of least significant bits). No
runtime exception occurs despite the loss.
In this noncompliant example, a large value of typelong intis converted to a
value of typefloatwithout ensuring it is representable in the type:
"""
severity = "Low"
likelihood = "Unlikely"
priority = "P2"
level = "L3"
cert_version = "2016 Edition (Wiki)"
last_modified = "Oct 29, 2025"
[rules.cert_c.FLP36-C]
enabled = true
[references]
wiki = "https://wiki.sei.cmu.edu/confluence/display/c/FLP36-C.+Preserve+precision+when+converting+integral+values+to+floating-point+type"
cwe = []