NAME¶
s2cc - Scheme to C compiler
SYNTAX¶
s2cc [ option ] ... file ...
DESCRIPTION¶
The
s2cc command (previously known as
scc) invokes a Scheme
compiler which accepts the language defined in the essential portions of
Revised4 Report on the Algorithmic Language Scheme, with minor
constraints and some additions. The compiler produces C source files which are
then compiled using the system's C compiler to produce conventional
.o
and
a.out files. The C code produced by this compiler may be intermixed
with other C code or code written in other languages.
OPTIONS¶
These options are accepted by
s2cc. Other options will be assumed to be
options of the system's C compiler and they will be passed to it when it is
invoked.
- -cc C compiler
- Compile the Scheme compiler produced C code with C
compiler. If this flag is not supplied, then the C compiler cc
will be used.
- -C
- Compile the Scheme programs found in the files
source.sc and leave the resulting code in source.c files. No
further operations are performed.
- -I directory
- Specifies a directory to be searched by include for source
files.
- -f symbol value
- Define the compile-time constant symbol to
value. This is equivalent to the construct (define-constant
symbol value) appearing in the Scheme source.
- -i
- Combine the source and object files into a Scheme
interpreter. The module name for each Scheme source file is automatically
determined. Module names for previously compiled modules must be specified
using the -m option.
- -m module-name
- Specifies the name of a previously compiled module. Note
that the Scheme compiler will downshift the alphabetic characters in the
module-name. Modules are initialized in the order that the
-m flags appear.
- -Ob
- Optimize code by omitting bounds checks on vectors and
strings.
- -Og
- Optimize code by omitting stack trace-back code.
- -On
- Optimize code by assuming that all numbers are fixed
point.
- -Ot
- Optimize code by omitting type error checks.
- -pg
- Produce profiled code for run-time measurement using
gprof(1). The profiled library is used in lieu of the standard
Scheme library.
- -scgc statflag
- Enables garbage collection statistics. If set to 1, then
garbage collection statistics will be printed. The default is 0, that will
result in no statistics.
- -sch heap
- Specifies the compiler's initial heap size in megabytes.
The default is system dependent.
- -scl percent
- Specifies the percent of the heap allocated after a
generational garbage collection that will force a full collection. The
default is 40.
- -scmh heap
- Specifies the compiler's maximum heap size in megabytes.
The default is five times the initial size of the heap.
- -LIBDIR directory
- Specifies a directory containing the files: predef.sc,
objects.h, libs2c.a, and optionally libs2c_p.a.
- -log
- Logs information internal to the compiler to the C source
file produced by the compiler. Each type of information is controlled by a
flag: -source, -macro, -expand, -closed,
-transform, -lambda, -tree, -lap,
-peep. The flag -log is equivalent to specifying the flags:
-source, -macro, -expand, -closed,
-transform, -lambda, -tree.
ENVIRONMENT VARIABLES¶
The items controlled by
-sc.. flags can also be controlled by environment
variables. If both the flag and the environment variable are provided, then
the flag's value will be used.
- SCGCINFO
- Controls the reporting of garbage collection statistics to
the standard error file. If set to 1, then garbage collection statistics
will be printed. The default setting is 0 that will not print the
statistics.
- SCHEAP
- Specifies the initial size of the heap in megabytes. The
default heap size is system dependent.
- SCLIMIT
- Specifies the percent of the heap allocated after a
generational garbage collection that will force a full collection. The
default is 40.
- SCMAXHEAP
- Specifies the maximum size of the heap in megabytes.
Following the command options come one or more file names.
- name.sc
- Scheme source. Scheme source files will be compiled into C
files with the name name.c.
- name.c
- C source.
- name.s
- Assembly language source.
- name.o
- Object file which may have been generated by any
compiler.
- name.a
- Object file archive which may have been generated by any
compiler.
DIAGNOSTICS¶
The disgnostic messages produced by the compiler are printed on the standard
error file.
FILES¶
/.../schemetoc/... source and documentation
/.../libs2c.a library
/.../libs2c_p.a profiled library (optional)
/.../s2cc shell script
/.../s2ccomp compiler
/.../predef.sc predefined functions
/.../objects.h definitions "#include'd" in the C code
SC-TO-C.c temporary C source file
source.S2C temporary C source file
SC-TO-C.o temporary object file
LIMITATIONS¶
When the compiler is able to identify every call to a procedure, it is able to
generate it "in-line", and perform tail calls by using
"goto". This analysis covers most loops, conditional expressions,
and finite state machines. For non-tail recursive calls, the code generated by
the compiler uses the standard C mechanisms for procedure call and return.
This therefore requires that each top-level Scheme procedure, and any Scheme
procedure which has more than one call which is not tail-recursive be compiled
into its own C procedure. Calls to such procedures will be tail-recursive if
and only if the host C compiler optimizes tail-recursion.
SEE ALSO¶
Harold Abelson and Gerald Jay Sussman with Julie Sussman,
Structure and
Interpretation of Computer Programs, The MIT Press.
William Clinger and Jonathan Rees (Editors),
Revised4 Report on the
Algorithmic Language Scheme, LISP Pointers, Volume IV, Number 3,
July-September 1991. PostScript for this file is included in the software
distribution.
Jerry D. Smith,
An Introduction to Scheme, Prentice Hall, Inc. Chapter
notes for using this text with Scheme->C are included in the software
distribution.
R. Kent Dybvig,
The SCHEME Programming Language, Prentice Hall, Inc.
Daniel P. Friedman and Matthias Felleisen,
The Little LISPer, MIT Press.
Joel F. Bartlett,
Scheme->C a Portable Scheme-to-C Compiler, WRL
Research Report 89/1.
Additional documentation is included in the software distribution.
s2ci(1)
http://alioth.debian.org/projects/scheme2c/