release [pending]
   - Abort on line numbering or column numbering overflow. Line
     numbers are limited to values that fit in "unsigned int". Also
     reject input lines longer than 2^32-1 characters. It seems
     reasonable to presume that any input that violates these
     constraints is someone screwing around and not a serious attempt
     to compile or preprocess anything useful. Done in response to
     n2129, but without getting into any of the silliness found there.
   - Recognize __ia64__ for IA64 builds.

release 0.5.2 (20160904)
   - Fix typo in -U usage message, noticed by Joerg.
   - Add a -debuglog option to send an execution trace to a file.
     Intended to be used when debugging imake templates and other
     complex input, not for debugging tradcpp itself.

release 0.5.1 (20150612)
   - Fix a stupid regression in 0.5 that causes it to not recognize a
     pile of options.
   - Fix output corruption caused by mishandling which macros are
     currently in use. In particular, "curmacro" is only valid while
     we're parsing a macro name and arguments, and can change once we
     start expanding, so don't use it to clear the in-use flag. This
     problem has been around all along but was only just exposed.
   - Also don't set curmacro to null after calling expand_domacro as
     that can cause us to think a macro name we just read is defined().
     This one was introduced in 0.5.
   - Don't use "remove" as a local variable as gcc 4.1 gets upset
     about it vs. remove(3) in stdio.h.

release 0.5 (20150612)
   - Don't report unclosed comments as "No newline at end of file".
   - Don't rely on <stdbool.h> existing, as (predictably) it doesn't
     work on Solaris.
   - Similarly, don't rely on C11 anonymous unions as the Solaris
     compiler vomits on them.
   - Typo fix in man page from Jason McIntyre; and change "Usage" to
     "usage" in usage for pedantic reasons, from Igor Sobrado.
   - Accept "-" as either input or output file name to mean stdin or
     stdout respectively. Suggested by Jonathan Gray.
   - Fix output spacing behavior to match gcc when newlines appear in or
     while looking for macro arguments. Partly from Joerg Sonnenberger.
   - Implement __FILE__ and __LINE__ macros. Mostly from Joerg Sonnenberger.
   - Implement #line. Partly from Joerg Sonnenberger.
   - Declare usage() with PF(). From wiz.

release 0.4 (20130713)
   - Fix stupid build problem introduced in 0.3.1.
   - Accept and ignore -m32, which imake issues willy-nilly on a bunch
     of platforms. I thought this had already been done, but apparently
     not.
   - Don't use the <err.h> functions. There are still people out there
     using legacy systems missing them.
   - Sort out some more issues pertaining to handling quoted strings.
   - Add some more tests.

release 0.3.1 (20130709)
   - Don't leak memory and assert if a bad command-line option comes
     after a -D or a -include foo.
   - Since imake is a principal application for tradcpp and imake carefully
     hides what it's doing when you run it, when rejecting an invalid option
     be sure to report *what* that option is.

release 0.3 (20130616)
   - Don't eval the control expression of the first #if of a block when
     already in a false block; it might not be valid. Reported by
     Baptiste Daroussin.
   - Don't recognize comments within character constants.
   - Don't recognize macro argument parentheses or commas within strings,
     or within character constants either.

release 0.2 (20130611)
   - auto-recognize more builtin PowerPC and mips macros
   - pass -Wunused (partly from Baptiste Daroussin)
   - allow absolute paths in include files (partly from Baptiste Daroussin)
   - don't use getprogname() in the name of portability
   - add tests arising from December 2010 tech-toolchain thread (one
     from der Mouse, one of mine)
   - clean out usage of sys/cdefs.h macros and don't use the implementation
     namespace
   - make -Wcomment work again
   - fix handling of relative includes
   - provide a man page
   - other minor improvements

release 0.1 (20130610)
   - first release, works with at least some imake templates