Re: signed is undefined and has been since 1992 (in GCC)

[Gabriel Dos Reis <gdr@integrable-solutions.net>]

Georg Bauhaus <bauhaus@futureapps.de> writes:

| Gabriel Dos Reis wrote:
| > Robert Dewar <dewar@adacore.com> writes:
| > | Gabriel Dos Reis wrote:
| > | | But the whole idea of hardware semantics is bogus, since you are
| > | assuming some connection between C and the hardware which does not
| > | exist. C is not an assembly language.
| > If you live in a different world, you may not see the connection.
| 
| I'm not sure whether this isn't just C's self-fulfilling
| prophecy at work: Many C programmers think that C is a high level

self-fulfilling prophecy or not, would you deny that processor
specific ABIs are published and programmers expect compilers to follow
them?  GCC itself relies on such connection.

| assembly language (at least in my real world).
| They start using C as if it were...

Well, I would not say it is something unique to C programmers.
Recently we had a guest working on compiler verification and model
checking, deeply rooted in the ML community explain us the
architecture of their proof checker.  The heart of the proof checker,
the trusted part, is written in C instead of SML.  When the question
was asked as to why -- probably because people were surprised, given their
close tie to SML -- and the answer was simple:  even though it can be
claimed that the C type system is unsound and SML's is sound, C is
trustworthy (and preferred over SML for that curcial part of the proof
checker) because the mapping of the C code to the generated assembly
code is straighforward and amenable to inspection.

-- Gaby