Clang only allows you to use __attribute__((format)) on variadic functions. There are legit use cases for __attribute__((format)) on non-variadic functions, such as:
(1) variadic templates
```c++
template<typename… Args>
void print(const char *fmt, Args… &&args) __attribute__((format(1, 2))); // error: format attribute requires variadic function
```
(2) functions which take fixed arguments and a custom format:
```c++
void print_number_string(const char *fmt, unsigned number, const char *string) __attribute__((format(1, 2)));
// ^error: format attribute requires variadic function
void foo(void) {
print_number_string(“%08x %s\n”, 0xdeadbeef, “hello”);
print_number_string(“%d %s”, 0xcafebabe, “bar”);
}
```
This change allows Clang users to attach __attribute__((format)) to non-variadic functions, including functions with C++ variadic templates. It replaces the error with a GCC compatibility warning and improves the type checker to ensure that received arrays are treated like pointers (this is a possibility in C++ since references to template types can bind to arrays).
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D112579
rdar://84629099
This adds a new __freebsd_kprintf__ format string type, which enables
checking when used in __attribute__((format(...))) attributes. It can
check the FreeBSD kernel specific %b, %D, %r and %y specifiers, using
existing diagnostic messages. Also adds test cases for all these
specifiers.
Differential Revision: http://reviews.llvm.org/D7154
llvm-svn: 229921
method parameter, provide a note pointing at the parameter itself so
the user does not have to manually look for the function/method being
called and match up parameters to arguments. For example, we now get:
t.c:4:5: warning: incompatible pointer types passing 'long *' to
parameter of
type 'int *' [-pedantic]
f(long_ptr);
^~~~~~~~
t.c:1:13: note: passing argument to parameter 'x' here
void f(int *x);
^
llvm-svn: 102038