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dmd.chkformat

Check the arguments to printf and scanf against the format string.

Authors:

Walter Bright

License:

Boost License 1.0

Source chkformat.d

Documentation https://dlang.org/phobos/dmd_chkformat.html

Coverage https://codecov.io/gh/dlang/dmd/src/master/src/dmd/chkformat.d

bool checkPrintfFormat(ref const Loc loc, scope const char[] format, scope Expression[] args, bool isVa_list);

Check that arguments to a printf format string are compatible with that string. Issue errors for incompatibilities.

Follows the C99 specification for printf.

Takes a generous, rather than strict, view of compatiblity. For example, an unsigned value can be formatted with a signed specifier.

Diagnosed incompatibilities are:

1. incompatible sizes which will cause argument misalignment 2. deferencing arguments that are not pointers 3. insufficient number of arguments 4. struct arguments 5. array and slice arguments 6. non-pointer arguments to s specifier 7. non-standard formats 8. undefined behavior per C99

Per the C Standard, extra arguments are ignored.

No attempt is made to fix the arguments or the format string.

Parameters:

Loc `loc`	location for error messages
char[] `format`	format string
Expression[] `args`	arguments to match with format string
bool `isVa_list`	if a "v" function (format check only)

Returns:

true if errors occurred

References C99 7.19.6.1 http://www.cplusplus.com/reference/cstdio/printf/

bool checkScanfFormat(ref const Loc loc, scope const char[] format, scope Expression[] args, bool isVa_list);

Check that arguments to a scanf format string are compatible with that string. Issue errors for incompatibilities.

Follows the C99 specification for scanf.