15.3.25 GCC internal Format Strings

These format strings are used inside the GCC sources. In such a format string, a directive starts with ‘%’, is optionally followed by a size specifier ‘l’, an optional flag ‘+’, another optional flag ‘#’, and is finished by a specifier: ‘%’ denotes a literal percent sign, ‘c’ denotes a character, ‘s’ denotes a string, ‘i’ and ‘d’ denote an integer, ‘o’, ‘u’, ‘x’ denote an unsigned integer, ‘.*s’ denotes a string preceded by a width specification, ‘H’ denotes a ‘location_t *’ pointer, ‘D’ denotes a general declaration, ‘F’ denotes a function declaration, ‘T’ denotes a type, ‘A’ denotes a function argument, ‘C’ denotes a tree code, ‘E’ denotes an expression, ‘L’ denotes a programming language, ‘O’ denotes a binary operator, ‘P’ denotes a function parameter, ‘Q’ denotes an assignment operator, ‘V’ denotes a const/volatile qualifier.