GdJpegQualityOutsideSupportedRange

error native on by default

Group: Probable bugs

Identify imagejpeg quality argument known integer outside -1 through100; retain -1 default sentinel.

Detection

• Report imagejpeg quality argument known integer outside -1 through100; retain -1 default sentinel.
• Resolve builtin functions, classes, constants and methods, including imports and supported named arguments. Follow only bounded local facts within one lexical scope. Receiver and argument provenance must establish the specific API contract; variable names and comments never prove intent.
• Report one finding per violating operation. A reachable path, unchanged value identity and applicable API behavior are required. Intervening mutation, unknown calls involving tracked values, escaped aliases or exhausted analysis budgets invalidate proof.
• D4. A quality passed as a variable is no longer proven once that variable, or a variable it was copied from by plain assignment, can change outside the tracked assignments earlier in the same scope than the argument: it is incremented or decremented (++/--, prefix or postfix), a closure defined there captures it by reference, or extract() or single-argument parse_str() writes the local symbol table. The same construct written after the call does not affect it, and neither do steps on other variables or on same-named locals of a nested function, by-value closure or arrow function.

Exceptions (no report)

• Exclude unresolved required symbols, user-defined lookalikes, incomplete syntax, unknown required values and unsupported versions.
• No report when D4 applies: $quality = 101; do { $quality--; imagejpeg($image, $path, $quality); } while (...) never passes 101.
• Both @custos-ignore GdJpegQualityOutsideSupportedRange and @noinspection GdJpegQualityOutsideSupportedRange suppress this native rule.

Fix

None. A repair requires a semantic decision or application error-handling policy.

PHP versions

Available in PHP 5.3–8.5 where the referenced API exists. Do not apply extension contracts when the resolved API is unavailable. Gate syntax and version-specific behavior to the configured target.

Configure

In custos.json:

{
  "rules": {
    "GdJpegQualityOutsideSupportedRange": {
      "enabled": false
    }
  }
}

Suppress

Before the statement or declaration (or the first statement of the file):

// @custos-ignore GdJpegQualityOutsideSupportedRange