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</P>

<PRE>
League for Programming Freedom
1 Kendall Square #143
P.O. Box 9171
Cambridge, MA 02139
</PRE>

<P>
You can also send electronic mail to <CODE>[e-mail]</CODE>.

</P>
<P>
In addition to joining the League, here are some suggestions from the
League for other things you can do to protect your freedom to write
programs:

</P>

<UL>
<LI>

Tell your friends and colleagues about this issue and how it threatens
to ruin the computer industry.

<LI>

Mention that you are a League member in your <TT>`.signature'</TT>, and
mention the League's email address for inquiries.

<LI>

Ask the companies you consider working for or working with to make
statements against software monopolies, and give preference to those
that do.

<LI>

When employers ask you to sign contracts giving them copyright on your
work, insist on a clause saying they will not claim the copyright covers
imitating the interface.

<LI>

When employers ask you to sign contracts giving them patent rights,
insist on clauses saying they can use these rights only defensively.
Don't rely on "company policy," since that can change at any time;
don't rely on an individual executive's private word, since that person
may be replaced.  Get a commitment just as binding as the commitment
they get from you.

<LI>

Write to Congress to explain the importance of these issues.


<PRE>
House Subcommittee on Intellectual Property
2137 Rayburn Bldg
Washington, DC 20515

Senate Subcommittee on Patents, Trademarks and Copyrights
United States Senate
Washington, DC 20510
</PRE>

(These committees have received lots of mail already; let's give them
even more.)
</UL>

<P>
Democracy means nothing if you don't use it.  Stand up and be counted!

</P>


<H1><A NAME="SEC7" HREF="gcc_toc.html#TOC7">Compile C, C++, or Objective C</A></H1>

<P>
<A NAME="IDX1"></A>
The C, C++, and Objective C versions of the compiler are integrated; the
GNU C compiler can compile programs written in C, C++, or Objective C.

</P>
<P>
<A NAME="IDX2"></A>
"GCC" is a common shorthand term for the GNU C compiler.  This is both
the most general name for the compiler, and the name used when the
emphasis is on compiling C programs.

</P>
<P>
<A NAME="IDX3"></A>
<A NAME="IDX4"></A>
When referring to C++ compilation, it is usual to call the compiler
"G++".  Since there is only one compiler, it is also accurate to call
it "GCC" no matter what the language context; however, the term
"G++" is more useful when the emphasis is on compiling C++ programs.

</P>
<P>
We use the name "GNU CC" to refer to the compilation system as a
whole, and more specifically to the language-independent part of the
compiler.  For example, we refer to the optimization options as
affecting the behavior of "GNU CC" or sometimes just "the compiler".

</P>
<P>
Front ends for other languages, such as Ada 9X, Fortran, Modula-3, and
Pascal, are under development.  These front-ends, like that for C++, are
built in subdirectories of GNU CC and link to it.  The result is an
integrated compiler that can compile programs written in C, C++,
Objective C, or any of the languages for which you have installed front
ends.

</P>
<P>
In this manual, we only discuss the options for the C, Objective-C, and
C++ compilers and those of the GNU CC core.  Consult the documentation
of the other front ends for the options to use when compiling programs
written in other languages.

</P>
<P>
<A NAME="IDX5"></A>
<A NAME="IDX6"></A>
<A NAME="IDX7"></A>
G++ is a <EM>compiler</EM>, not merely a preprocessor.  G++ builds object
code directly from your C++ program source.  There is no intermediate C
version of the program.  (By contrast, for example, some other
implementations use a program that generates a C program from your C++
source.)  Avoiding an intermediate C representation of the program means
that you get better object code, and better debugging information.  The
GNU debugger, GDB, works with this information in the object code to
give you comprehensive C++ source-level editing capabilities
(see section `C and C++' in <CITE>Debugging with GDB</CITE>).

</P>



<H1><A NAME="SEC8" HREF="gcc_toc.html#TOC8">GNU CC Command Options</A></H1>
<P>
<A NAME="IDX8"></A>
<A NAME="IDX9"></A>
<A NAME="IDX10"></A>

</P>
<P>
When you invoke GNU CC, it normally does preprocessing, compilation,
assembly and linking.  The "overall options" allow you to stop this
process at an intermediate stage.  For example, the <SAMP>`-c'</SAMP> option
says not to run the linker.  Then the output consists of object files
output by the assembler.

</P>
<P>
Other options are passed on to one stage of processing.  Some options
control the preprocessor and others the compiler itself.  Yet other
options control the assembler and linker; most of these are not
documented here, since you rarely need to use any of them.

</P>
<P>
<A NAME="IDX11"></A>
Most of the command line options that you can use with GNU CC are useful
for C programs; when an option is only useful with another language
(usually C++), the explanation says so explicitly.  If the description
for a particular option does not mention a source language, you can use
that option with all supported languages.

</P>
<P>
<A NAME="IDX12"></A>
See section <A HREF="gcc.html#SEC11">Compiling C++ Programs</A>, for a summary of special
options for compiling C++ programs.

</P>
<P>
<A NAME="IDX13"></A>
<A NAME="IDX14"></A>
The <CODE>gcc</CODE> program accepts options and file names as operands.  Many
options have multiletter names; therefore multiple single-letter options
may <EM>not</EM> be grouped: <SAMP>`-dr'</SAMP> is very different from <SAMP>`-d
-r'</SAMP>.

</P>
<P>
<A NAME="IDX15"></A>
<A NAME="IDX16"></A>
You can mix options and other arguments.  For the most part, the order
you use doesn't matter.  Order does matter when you use several options
of the same kind; for example, if you specify <SAMP>`-L'</SAMP> more than once,
the directories are searched in the order specified.

</P>
<P>
Many options have long names starting with <SAMP>`-f'</SAMP> or with
<SAMP>`-W'</SAMP>---for example, <SAMP>`-fforce-mem'</SAMP>,
<SAMP>`-fstrength-reduce'</SAMP>, <SAMP>`-Wformat'</SAMP> and so on.  Most of
these have both positive and negative forms; the negative form of
<SAMP>`-ffoo'</SAMP> would be <SAMP>`-fno-foo'</SAMP>.  This manual documents
only one of these two forms, whichever one is not the default.

</P>



<H2><A NAME="SEC9" HREF="gcc_toc.html#TOC9">Option Summary</A></H2>

<P>
Here is a summary of all the options, grouped by type.  Explanations are
in the following sections.

</P>
<DL COMPACT>

<DT><EM>Overall Options</EM>
<DD>
See section <A HREF="gcc.html#SEC10">Options Controlling the Kind of Output</A>.

<PRE>
-c  -S  -E  -o <VAR>file</VAR>  -pipe  -v  -x <VAR>language</VAR> 
</PRE>

<DT><EM>C Language Options</EM>
<DD>
See section <A HREF="gcc.html#SEC12">Options Controlling C Dialect</A>.

<PRE>
-ansi  -fallow-single-precision  -fcond-mismatch
-fno-asm  -fno-builtin  -fsigned-bitfields
-fsigned-char  -funsigned-bitfields  -funsigned-char
-fwritable-strings  -traditional  -traditional-cpp
-trigraphs
</PRE>

<DT><EM>C++ Language Options</EM>
<DD>
See section <A HREF="gcc.html#SEC13">Options Controlling C++ Dialect</A>.

<PRE>
-fall-virtual  -fdollars-in-identifiers
-felide-constructors  -fenum-int-equiv
-fexternal-templates  -fhandle-signatures
-fmemoize-lookups  -fno-default-inline
-fno-gnu-keywords  -fnonnull-objects
-foperator-names  -fstrict-prototype
-fthis-is-variable  -nostdinc++
-traditional  +e<VAR>n</VAR>
-fenum-int-equiv -fexternal-templates  -ffor-scope -fno-for-scope
-fhandle-signatures -fmemoize-lookups  -fno-default-inline -fno-gnu-keywords
-fnonnull-objects  -foperator-names  -fstrict-prototype
-fthis-is-variable -nostdinc++ -traditional  +e<VAR>n</VAR>
</PRE>

<DT><EM>Warning Options</EM>
<DD>
See section <A HREF="gcc.html#SEC14">Options to Request or Suppress Warnings</A>.

<PRE>
-fsyntax-only  -pedantic  -pedantic-errors
-w  -W  -Wall  -Waggregate-return  -Wbad-function-cast
-Wcast-align -Wcast-qual  -Wchar-subscript  -Wcomment
-Wconversion -Wenum-clash  -Werror  -Wformat
-Wid-clash-<VAR>len</VAR>  -Wimplicit  -Wimport  -Winline
-Wlarger-than-<VAR>len</VAR>  -Wmissing-declarations
-Wmissing-prototypes  -Wnested-externs
-Wno-import  -Woverloaded-virtual -Wparentheses
-Wpointer-arith  -Wredundant-decls -Wreorder 
-Wreturn-type  -Wshadow  -Wstrict-prototypes
-Wswitch  -Wsynth  -Wtemplate-debugging  -Wtraditional
-Wtrigraphs -Wuninitialized  -Wunused  -Wwrite-strings
</PRE>

<DT><EM>Debugging Options</EM>
<DD>
See section <A HREF="gcc.html#SEC15">Options for Debugging Your Program or GNU CC</A>.

<PRE>
-a  -ax  -d<VAR>letters</VAR>  -fpretend-float
-g  -g<VAR>level</VAR> -gcoff  -gdwarf  -gdwarf+
-ggdb  -gstabs  -gstabs+  -gxcoff  -gxcoff+
-p  -pg  -print-file-name=<VAR>library</VAR>  
-print-libgcc-file-name  -print-prog-name=<VAR>program</VAR>
-save-temps
-print-prog-name=<VAR>program</VAR>  -print-search-dirs  -save-temps
</PRE>

<DT><EM>Optimization Options</EM>
<DD>
See section <A HREF="gcc.html#SEC16">Options That Control Optimization</A>.

<PRE>
-fcaller-saves  -fcombine-statics -fcse-follow-jumps  -fcse-skip-blocks
-fdelayed-branch   -fexpensive-optimizations  
-ffast-math  -ffloat-store  -fforce-addr  -fforce-mem
-ffunction-sections -finline-functions  -fkeep-inline-functions  
-fno-default-inline  -fno-defer-pop  -fno-function-cse
-fno-inline  -fno-peephole  -fomit-frame-pointer  
-frerun-cse-after-loop  -fschedule-insns  
-fschedule-insns2  -fshorten-lifetimes -fstrength-reduce  -fthread-jumps 
-funroll-all-loops  -funroll-loops
-O  -O0  -O1  -O2  -O3
</PRE>

<DT><EM>Preprocessor Options</EM>
<DD>
See section <A HREF="gcc.html#SEC17">Options Controlling the Preprocessor</A>.

<PRE>
-A<VAR>question</VAR>(<VAR>answer</VAR>)  -C  -dD  -dM  -dN
-D<VAR>macro</VAR>[=<VAR>defn</VAR>]  -E  -H
-idirafter <VAR>dir</VAR>
-include <VAR>file</VAR>  -imacros <VAR>file</VAR>
-iprefix <VAR>file</VAR>  -iwithprefix <VAR>dir</VAR>
-iwithprefixbefore <VAR>dir</VAR>  -isystem <VAR>dir</VAR>
-M  -MD  -MM  -MMD  -MG  -nostdinc  -P  -trigraphs
-undef  -U<VAR>macro</VAR>  -Wp,<VAR>option</VAR>
</PRE>

<DT><EM>Assembler Option</EM>
<DD>
See section <A HREF="gcc.html#SEC18">Passing Options to the Assembler</A>.

<PRE>
-Wa,<VAR>option</VAR>
</PRE>

<DT><EM>Linker Options</EM>
<DD>
See section <A HREF="gcc.html#SEC19">Options for Linking</A>.

<PRE>
<VAR>object-file-name</VAR>  -l<VAR>library</VAR>
-nostartfiles  -nodefaultlibs  -nostdlib  
-s  -static  -shared  -symbolic  
-Wl,<VAR>option</VAR>  -Xlinker <VAR>option</VAR>
-u <VAR>symbol</VAR>
</PRE>

<DT><EM>Directory Options</EM>
<DD>
See section <A HREF="gcc.html#SEC20">Options for Directory Search</A>.

<PRE>
-B<VAR>prefix</VAR>  -I<VAR>dir</VAR>  -I-  -L<VAR>dir</VAR>
</PRE>

<DT><EM>Target Options</EM>
<DD>
See section <A HREF="gcc.html#SEC21">Specifying Target Machine and Compiler Version</A>.

<PRE>
-b <VAR>machine</VAR>  -V <VAR>version</VAR>
</PRE>

<DT><EM>Machine Dependent Options</EM>
<DD>
See section <A HREF="gcc.html#SEC22">Hardware Models and Configurations</A>.

<PRE>
<EM>M680x0 Options</EM>
-m68000  -mc68000  -m68020  -mc68020