The previous commit removed the code related to the internal symbol
table. On platforms where available, we can now use backtrace_symbols()
to print more verbose symbols table to the output.
As there's now general availability of backtrace() and
backtrace_symbols() functions (see below), the commit also removes the
usage of glibc internals and the custom stack tracing.
* backtrace(), backtrace_symbols(), and backtrace_symbols_fd() are
provided in glibc since version 2.1.
* backtrace(), backtrace_symbols(), and backtrace_symbols_fd() first
appeared in Mac OS X 10.5.
* The backtrace() library of functions first appeared in NetBSD 7.0 and
FreeBSD 10.0.
Mostly, several functions that take pointers as arguments, almost
always char * pointers, had those pointers qualified with "const".
Those that returned pointers to previously const-qualified arguments
had their return values qualified as const. Some structure members
were qualified as const to retain that attribute from the variables
from which they were assigned.
The macro DE_CONST was added to isc/util.h to deal with a handful of very
special places where something is qualified as const but really needs to have
its const qualifier removed.
Also cleaned up a few places where variable names clashed with reserved
identifiers. (Which mostly works fine, but strictly speaking is undefined
by the standard.)
Minor other ISC style cleanups.
Cleanup of redundant/useless header file inclusion.
ISC style lint, primarily for function declarations and standalone
comments -- ie, those that appear on a line without any code, which
should be written as follows:
/*
* This is a comment.
*/
