DCL41-C. Do not refer to a static object in an external inline function

The C Standard, subclause 6.7.4 paragraph 3, says:

An inline definition of a function with external linkage shall not contain a definition of a modifiable object with static or thread storage duration, and shall not contain a reference to an identifier with internal linkage.

Noncompliant Code Example

This code refers to a static constant inside an external inline function:

static const double C = -0.00138867637746099294692;
extern inline void func(double a) {
  double b = a * C;
  /* ... */
}

Compliant Solution

This compliant solution does not declare the constant to be static.

const double C = -0.00138867637746099294692;
extern inline void func(double a) {
  double b = a * C;
  /* ... */
}

Risk Assessment

Related Vulnerabilities

Search for vulnerabilities resulting from the violation of this rule on the CERT website.

Bibliography