[tree-ssa] Why are bools cast to int in conditionals?

[Paul Koning]

>>>>> "Joseph" == Joseph S Myers <jsm@polyomino.org.uk> writes:

 Joseph> On Thu, 22 Apr 2004, Paul Koning wrote:
 >> The trouble with that is that promotion to int is in fact
 >> language-specific -- C/C++ may define things that way, but most
 >> other high level languages don't.  Not that modula-3 or pascal is
 >> a high visibility front-end, but I don't think that viewing this
 >> issue as language-INdependent is right.

 Joseph> Other languages convert bool to int yielding values other
 Joseph> than 0 (false) and 1 (true), or otherwise promote them such
 Joseph> that a comparison of promoted / converted values can't be
 Joseph> narrowed to one of narrower types?  The fact that there's an
 Joseph> implicit promotion may be language-dependent - each front end
 Joseph> should build trees reflecting what the language's rules are -
 Joseph> but the question is whether the transformation narrowing an
 Joseph> operation on promoted types is also language-dependent.

I sure don't understand this.  In most languages (Pascal, Algol, etc.)
Boolean is a first-class type, and the notion of implicit conversion
to int simply does not exist.

Do you mean that the compiler can invent such an implicit conversion
as a way to transform the input into a language-independent form?
That may be true, and the C rule may be a fine way to do that.  

But that isn't the same as saying that there's an implicit conversion
notion in the language.  Otherwise bool == int would be a legal
operation in every language -- and that is not the case.

	  paul