A clang user pointed out that messages for the static analyzer undefined
assignment checker use the term ‘garbage’, which might have a negative
connotation to some users. This change updates the messages to use the
term ‘uninitialized’. This is the usual reason why a value is undefined
in the static analyzer and describes the logical error that a programmer
should take action to fix.
Out-of-bounds reads can also produce undefined values in the static
analyzer. The right long-term design is to have to the array bounds
checker cover out-of-bounds reads, so we do not cover that case in the
updated messages. The recent improvements to the array bounds checker
make it a candidate to add to the core set of checkers.
rdar://133418644
Add basic support for `builtin_*_overflow` primitives.
These helps a lot for checking custom calloc-like functions with
inlinable body. Without such support code like
```c
#include <stddef.h>
#include <stdlib.h>
static void *myMalloc(size_t a1, size_t a2)
{
size_t res;
if (__builtin_mul_overflow(a1, a2, &res))
return NULL;
return malloc(res);
}
void test(void)
{
char *ptr = myMalloc(10, 1);
ptr[20] = 10;
}
````
does not trigger any warnings.
