ISO Pascal reference manual

Chapter 6
The form `x x x x' will be used to represent memory whose contents are not
defined for the purposes of an illustration.
6.2 Conformance
The Pascal implementation conforms very closely to the code mechanisms
defined in the Inter-Language Calling Standard. In particular the way in
which parameters are passed is exactly in accordance with the standard, as
far as Integers, Reals, Records and Booleans are concerned. Similarly,
results (such as Pascal allows, e.g. not Records) are returned in the standard
manner. Since Pascal does not have a String type, inter-facing with
languages which do (and with Panos) typically involves a little work in
mapping strings onto a corresponding Pascal structure, but will normally be
quite straightforward (i.e. there is no fundamental obstacle to doing this).
Further, returning Record results is very simply mapped onto updating a
VAR parameter. Full details of these mechanisms will now be given.
6.2.2 Types
Here is a full description of how Pascal types are mapped onto the
architecture of the 32000 series:
Integer
32-bit quantity, aligned on 4-byte boundary. A variable of type Integer may
hold any 32-bit signed value, except that when code is compiled with checks
for assignment included (the default), the value 16_80808080 is reserved for
the purpose of detecting use of a variable before it has been assigned to.
Real
64-bit double precision (32000 `-L' type), aligned on a 4-byte address
boundary. See note below on the use of 32-bit reals. If assignment checks
have been included in the compiled program then real variables are
initialised with the reserved pattern 16_8080808080808080.
32 Pascal Issue 1