Unbraced statements spanning multiple lines has been shown in many
projects to contribute to the introduction of bugs and a failure
to catch them in review, especially for maintenance on infrequently
modified code.
Most, but not all, of the existing practice in the codebase were not
cases that I would have expected to eventually result in bugs but
applying it as a rule makes it easier for other people to safely
contribute.
I'm not aware of any such evidence for the case with the statement
on a single line, but some people strongly prefer to never do that
and the opposite rule of "_always_ use a single line for single
statement blocks" isn't a reasonable rule for formatting reasons.
Might as well brace all these too, since that's more universally
acceptable.
[In any case, I seem to have introduced the vast majority of the
single-line form (as they're my preference where they fit).]
This also removes a broken test which is no longer needed.
C doesn't include the null in an array initilized from a
string literal if it doesn't fit, in C++ this is invalid.
The vararray style prototypes and init+calc also changed in
this commit are not C89 enough for some tools.
GCC (and clang) supports extensions to annotate functions so that their
results must be used and so that their arguments can't be statically
provable to be null. If a caller violates these requirements they
get a warning, so this helps them write correct code.
I deployed this in libopus a couple years ago with good success, and
the implementation here is basically copied straight from that.
One consideration is that the non-null annotation teaches the optimizer
and will actually compile out runtime non-nullness checks as dead-code.
Since this is usually not whats wanted, the non-null annotations are
disabled when compiling the library itself.
The commit also removes some dead inclusions of assert.h and introduces
compatibility macros for restrict and inline in preparation for some
portability improvements.
