tidy - bugprone-suspicious-missing-comma — Extra Clang Tools 22.0.0git documentation (original) (raw)

String literals placed side-by-side are concatenated at translation phase 6 (after the preprocessor). This feature is used to represent long string literal on multiple lines.

For instance, the following declarations are equivalent:

const char* A[] = "This is a test"; const char* B[] = "This" " is a " "test";

A common mistake done by programmers is to forget a comma between two string literals in an array initializer list.

const char* Test[] = { "line 1", "line 2" // Missing comma! "line 3", "line 4", "line 5" };

The array contains the string “line 2line3” at offset 1 (i.e. Test[1]). Clang won’t generate warnings at compile time.

This check may warn incorrectly on cases like:

const char* SupportedFormat[] = { "Error %s", "Code " PRIu64, // May warn here. "Warning %s", };

Options¶

SizeThreshold¶

An unsigned integer specifying the minimum size of a string literal to be considered by the check. Default is 5U.

RatioThreshold¶

A string specifying the maximum threshold ratio [0, 1.0] of suspicious string literals to be considered. Default is ".2".

MaxConcatenatedTokens¶

An unsigned integer specifying the maximum number of concatenated tokens. Default is 5U.