Limbo
compiles the named Limbo
files
into machine-independent object files for the Dis virtual machine.
Depending on the options, the compiler may create output
files or write information to its standard output.
Conventional files and their extensions include the following.
- file.b
- Limbo source file.
- file.dis
- Object code for the Dis virtual machine.
- file.m
- Limbo source file for
module
declarations.
- file.s
- Assembly code.
- file.sbl
- Symbolic debugging information.
With no options,
limbo
produces a
.dis
file for each
source file.
The compiler options are:
- -a
- Print on standard output
type definitions and call frames
useful for writing C language implementations of Limbo modules.
Suppresses normal output file generation.
- -C
- Mark the Dis object file to prevent run-time compilation.
- -c
- Mark the Dis object file to guarantee run-time compilation.
- -D flags
- Turn on debugging
flags.
Flags include
A
for arrays,
a
for
alt
statements,
b
for booleans,
C
for
case
body statements,
c
for
case
statements,
D
for use descriptors,
d
for declarations,
e
for expressions,
E
for extended expressions,
F
for function information,
f
for constant folding,
m
for modules,
n
for
nil
references,
P
for program counter manipulations,
r
for reference types,
S
for type signatures,
s
for a code generation summary,
T
for tuples,
t
for type checking,
and
v
for variable initialization.
- -e
- Increase the number of errors the compiler will report before exiting.
- -G
- Annotate assembly language output with debugging information.
A no-op unless
-S
is set.
- -g
- Generate debugging information for the input files and place it in a file
named by stripping any trailing
.b
from the input file name and appending
.sbl.
- -i
- Disable inlining of functions. Currently functions containing a
single return statement or two return statements and an if clause are candidates for inlining.
- -I dir
- An
include
file whose name does not begin with slash
is sought first relative to the working directory,
regardless of the source
file
argument.
If this fails,
limbo
sequences through directories named in
-I
options,
then searches in
/module.
An
include
file contains Limbo source code, normally holding one or more
module
declarations.
- -o obj
- Place output in file
obj
(allowed only if there is a single input
file).
The output file will hold either object or assembly code,
depending on
-S.
Default is to take the last element of the input file name,
strip any trailing
.b,
and append
.dis
for object code and
.s
for assembly code.
Thus, the default output file for
dir/mod.b
would be
mod.dis.
- -S
- Create assembly language output instead of object code.
- -T module
- Print on standard output C stub functions,
useful for implementing Limbo modules in the C language for linkage
with the interpreter.
- -t module
- Print on standard output
a table of runtime functions,
to link C language implementations of modules with the Limbo interpreter.
Suppresses normal output file generation.
- -w
- Print warning messages about unused variables, etc.
More w's (e.g., -ww) increase the pedantry of the checking.