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@ -65,7 +65,7 @@ Short options:
-O Optimize code -O Optimize code
-Oi Optimize code, inline more code -Oi Optimize code, inline more code
-Or Enable register variables -Or Enable register variables
-Os Inline some known functions -Os Inline some known functions
-T Include source as comment -T Include source as comment
-V Print the compiler version number -V Print the compiler version number
-W Suppress warnings -W Suppress warnings
@ -93,10 +93,7 @@ Here is a description of all the command line options:
This option disables any compiler exensions. Have a look at section 5 This option disables any compiler exensions. Have a look at section 5
for a discussion of compiler extensions. In addition, the macro for a discussion of compiler extensions. In addition, the macro
<verb> <tt/__STRICT_ANSI__/ is defined, when using one of these options.
__STRICT_ANSI__
</verb>
is defined, when using one of these options.
<tag><tt>--cpu CPU</tt></tag> <tag><tt>--cpu CPU</tt></tag>
@ -123,7 +120,7 @@ Here is a description of all the command line options:
<tag><tt>-g, --debug-info</tt></tag> <tag><tt>-g, --debug-info</tt></tag>
This will cause the compiler to insert a .DEBUGINFO command into the This will cause the compiler to insert a <tt/.DEBUGINFO/ command into the
generated assembler code. This will cause the assembler to include all generated assembler code. This will cause the assembler to include all
symbols in a special section in the object file. symbols in a special section in the object file.
@ -139,8 +136,8 @@ Here is a description of all the command line options:
6502 has no provisions for sign extending characters (which is needed on 6502 has no provisions for sign extending characters (which is needed on
almost any load operation), this will make the code larger and slower. A almost any load operation), this will make the code larger and slower. A
better way is to declare characters explicitly as "signed" if needed. better way is to declare characters explicitly as "signed" if needed.
You can also use "#pragma signedchars" for better control of this option You can also use <tt/#pragma signedchars/ for better control of this option
(see section 7). (see section <ref id="pragmas" name="#pragmas">).
<tag><tt>-t target, --target target</tt></tag> <tag><tt>-t target, --target target</tt></tag>
@ -149,17 +146,16 @@ Here is a description of all the command line options:
determines things like the character set that is used for strings and determines things like the character set that is used for strings and
character constants. The following target systems are supported: character constants. The following target systems are supported:
none <itemize>
c64 <item>none
c128 <item>c64
ace (no library support) <item>c128
plus4 <item>plus4
cbm610 <item>cbm610 (all CBM series-II computers with 80 column video)
pet (all CBM PET systems except the 2001) <item>pet (all CBM PET systems except the 2001)
nes (Nintendo Entertainment System) <item>apple2
apple2 <item>geos
geos </itemize>
<tag><tt>-v, --verbose</tt></tag> <tag><tt>-v, --verbose</tt></tag>
@ -172,31 +168,35 @@ Here is a description of all the command line options:
Use static storage for local variables instead of storage on the stack. Use static storage for local variables instead of storage on the stack.
Since the stack is emulated in software, this gives shorter and usually Since the stack is emulated in software, this gives shorter and usually
faster code, but the code is no longer reentrant. The difference between faster code, but the code is no longer reentrant. The difference between
-Cl and declaring local variables as static yourself is, that <tt/-Cl/ and declaring local variables as static yourself is, that
initializer code is executed each time, the function is entered. So when initializer code is executed each time, the function is entered. So when
using using
<tscreen><verb>
void f (void) void f (void)
{ {
unsigned a = 1; unsigned a = 1;
... ...
} }
</verb></tscreen>
the variable a will always have the value 1 when entering the function the variable a will always have the value 1 when entering the function
and using -Cl, while in and using <tt/-Cl/, while in
<tscreen><verb>
void f (void) void f (void)
{ {
static unsigned a = 1; static unsigned a = 1;
.... ....
} }
</verb></tscreen>
the variable a will have the value 1 only the first time, the function the variable a will have the value 1 only the first time, the function
is entered, and will keep the old value from one call of the function to is entered, and will keep the old value from one call of the function to
the next. the next.
You may also use #pragma staticlocals to change this setting in your You may also use <tt/#pragma staticlocals/ to change this setting in your
sources (see section 7). sources (see section <ref id="pragmas" name="#pragmas">).
<tag><tt>-I dir, --include-dir dir</tt></tag> <tag><tt>-I dir, --include-dir dir</tt></tag>
@ -216,32 +216,35 @@ Here is a description of all the command line options:
Enable an optimizer run over the produced code. Enable an optimizer run over the produced code.
Using -Oi, the code generator will inline some code where otherwise a Using <tt/-Oi/, the code generator will inline some code where otherwise a
runtime functions would have been called, even if the generated code is runtime functions would have been called, even if the generated code is
larger. This will not only remove the overhead for a function call, but larger. This will not only remove the overhead for a function call, but will
will make the code visible for the optimizer. make the code visible for the optimizer.
-Or will make the compiler honor the "register" keyword. Local variables <tt/-Or/ will make the compiler honor the <tt/register/ keyword. Local
may be placed in registers (which are actually zero page locations). variables may be placed in registers (which are actually zero page
There is some overhead involved with register variables, since the old locations). There is some overhead involved with register variables, since
contents of the registers must be saved and restored. In addition, the the old contents of the registers must be saved and restored. In addition,
current implementation does not make good use of register variables, so the current implementation does not make good use of register variables, so
using -Or may make your program even slower and larger. Use with care! using <tt/-Or/ may make your program even slower and larger. Use with care!
Using -Os will force the compiler to inline some known functions from Using <tt/-Os/ will force the compiler to inline some known functions from
the C library like strlen. Note: This has two consequences: the C library like strlen. Note: This has two consequences:
<p>
* You may not use names of standard C functions in your own code. If <itemize>
you do that, your program is not standard compliant anyway, but <item>You may not use names of standard C functions in your own code. If you
using -Os will actually break things. do that, your program is not standard compliant anyway, but using
<tt/-Os/ will actually break things.
* The inlined string and memory functions will not handle strings or <p>
memory areas larger than 255 bytes. Similar, the inlined is..() <item>The inlined string and memory functions will not handle strings or
functions will not work with values outside char range. memory areas larger than 255 bytes. Similar, the inlined <tt/is..()/
functions will not work with values outside char range.
It is possible to concatenate the modifiers for -O. For example, to <p>
</itemize>
<p>
It is possible to concatenate the modifiers for <tt/-O/. For example, to
enable register variables and inlining of known functions, you may use enable register variables and inlining of known functions, you may use
-Ors. <tt/-Ors/.
<tag><tt>-T</tt></tag> <tag><tt>-T</tt></tag>
@ -273,8 +276,8 @@ the same base name, but with the extension replaced by ".s". The output
file contains assembler code suitable for the use with the ca65 macro file contains assembler code suitable for the use with the ca65 macro
assembler. assembler.
In addition to the paths named in the -I option on the command line, the In addition to the paths named in the <tt/-I/ option on the command line, the
directory named in the environment variable CC65_INC is added to the directory named in the environment variable <tt/CC65_INC/ is added to the
search path for include files on startup. search path for include files on startup.
@ -288,37 +291,44 @@ and the one defined by the ISO standard:
<item> The compiler allows single line comments that start with //. This <item> The compiler allows single line comments that start with //. This
feature is disabled in strict ANSI mode. feature is disabled in strict ANSI mode.
<p>
<item> The compiler allows unnamed parameters in parameter lists. The <item> The compiler allows unnamed parameters in parameter lists. The
compiler will not issue warnings about unused parameters that don't compiler will not issue warnings about unused parameters that don't
have a name. This feature is disabled in strict ANSI mode. have a name. This feature is disabled in strict ANSI mode.
<item> The compiler has some additional keywords:<p>
<tt/asm/, <tt/__asm__/, <tt/fastcall/, <tt/__fastcall__/, <tt/__AX__/,
<tt/__EAX__/, <tt/__func__/, <tt/__attribute__/
<p> <p>
<item> The compiler has some additional keywords:
<p>
<itemize>
<item><tt/asm/
<item><tt/__asm__/
<item><tt/fastcall/
<item><tt/__fastcall__/
<item><tt/__AX__/
<item><tt/__EAX__/
<item><tt/__func__/
<item><tt/__attribute__/
</itemize>
<p>
The keywords without the underlines are disabled in strict ANSI mode. The keywords without the underlines are disabled in strict ANSI mode.
<p>
<item> The datatypes "float" and "double" are not available. <item> The datatypes "float" and "double" are not available.
<p>
<item> The compiler does not support bit fields. <item> The compiler does not support bit fields.
<p>
<item> Initialization of local variables is only possible for scalar data <item> Initialization of local variables is only possible for scalar data
types (that is, not for arrays and structs). types (that is, not for arrays and structs).
<p>
<item> Because of the "wrong" order of the parameters on the stack, there is <item> Because of the "wrong" order of the parameters on the stack, there is
an additional macro needed to access parameters in a variable an additional macro needed to access parameters in a variable
parameter list in a C function. parameter list in a C function.
<p>
<item> Functions may not return structs. However, struct assignment *is* <item> Functions may not return structs. However, struct assignment *is*
possible. possible.
<p>
<item> Part of the C library is available only with fastcall calling <item> Part of the C library is available only with fastcall calling
conventions (see below). This means, that you may not mix pointers to conventions (see below). This means, that you may not mix pointers to
those functions with pointers to user written functions. those functions with pointers to user written functions.
<p>
</itemize> </itemize>
There may be some more minor differences, I'm currently not aware off. The There may be some more minor differences, I'm currently not aware off. The
@ -334,48 +344,42 @@ This cc65 version has some extensions to the ISO C standard.
<itemize> <itemize>
<item> The compiler allows // comments (like in C++ and in the proposed C9x <item> The compiler allows // comments (like in C++ and in the proposed C9x
standard). This feature is disabled by <tt/-A/. standard). This feature is disabled by <tt/-A/.
<item> The compiler allows to insert assembler statements into the output <item> The compiler allows to insert assembler statements into the output
file. The syntax is file. The syntax is
<p> <p>
<tt/asm (&lt;string literal&gt;) ;/ <tt/asm (&lt;string literal&gt;) ;/
<p> <p>
or
or <p>
<p>
<tt/__asm__ (&lt;string literal&gt;) ;/ <tt/__asm__ (&lt;string literal&gt;) ;/
<p> <p>
The first form is in the user namespace and is disabled if the <tt/-A/ The first form is in the user namespace and is disabled if the <tt/-A/
switch is given. switch is given.
The given string is inserted literally into the output file, and a The given string is inserted literally into the output file, and a
newline is appended. The statements in this string are not checked by newline is appended. The statements in this string are not checked by
the compiler, so be careful! the compiler, so be careful!
The asm statement may be used inside a function and on global file The asm statement may be used inside a function and on global file
level. level.
<item> There is a special calling convention named "fastcall". This calling <item> There is a special calling convention named "fastcall". This calling
convention is currently only usable for functions written in convention is currently only usable for functions written in
assembler. The syntax for a function declaration using fastcall is assembler. The syntax for a function declaration using fastcall is
<p>
<tt/&lt;return type&gt; fastcall &lt;function name&gt; (&lt;parameter list&gt;)/
<p> <p>
&lt;return type&gt; fastcall &lt;function name&gt; (&lt;parameter list&gt;) or
<p> <p>
<tt/&lt;return type&gt; __fastcall__ &lt;function name&gt; (&lt;parameter list&gt;)/
or
<p>
&lt;return type&gt; __fastcall__ &lt;function name&gt; (&lt;parameter list&gt;)
<p> <p>
An example would be An example would be
<p>
<tscreen><verb> <tt/void __fastcall__ f (unsigned char c)/
void __fastcall__ f (unsigned char c) <p>
</verb></tscreen>
The first form of the fastcall keyword is in the user namespace and is The first form of the fastcall keyword is in the user namespace and is
therefore disabled in strict ANSI mode. therefore disabled in strict ANSI mode.
@ -453,8 +457,7 @@ The compiler defines several macros at startup:
<tag><tt>__ATARI__</tt></tag> <tag><tt>__ATARI__</tt></tag>
This macro is defined if the target is one of the Atari computers This macro is defined if the target is one of the Atari computers
(400/800/130XL/800XL). Note that there is no runtime and C library support (400/800/130XL/800XL).
for atari systems.
<tag><tt>__APPLE2__</tt></tag> <tag><tt>__APPLE2__</tt></tag>
@ -474,29 +477,29 @@ The compiler defines several macros at startup:
<tag><tt>__STRICT_ANSI__</tt></tag> <tag><tt>__STRICT_ANSI__</tt></tag>
This macro is defined to 1 if the -A compiler option was given, and This macro is defined to 1 if the <tt/-A/ compiler option was given, and
undefined otherwise. undefined otherwise.
<tag><tt>__OPT__</tt></tag> <tag><tt>__OPT__</tt></tag>
Is defined if the compiler was called with the -O command line option. Is defined if the compiler was called with the <tt/-O/ command line option.
<tag><tt>__OPT_i__</tt></tag> <tag><tt>__OPT_i__</tt></tag>
Is defined if the compiler was called with the -Oi command line option. Is defined if the compiler was called with the <tt/-Oi/ command line option.
<tag><tt>__OPT_r__</tt></tag> <tag><tt>__OPT_r__</tt></tag>
Is defined if the compiler was called with the -Or command line option. Is defined if the compiler was called with the <tt/-Or/ command line option.
<tag><tt>__OPT_s__</tt></tag> <tag><tt>__OPT_s__</tt></tag>
Is defined if the compiler was called with the -Os command line option. Is defined if the compiler was called with the <tt/-Os/ command line option.
</descrip> </descrip>
<sect>#pragmas<p> <sect>#pragmas<label id="pragmas"><p>
The compiler understands some pragmas that may be used to change code The compiler understands some pragmas that may be used to change code
generation and other stuff. generation and other stuff.
@ -518,8 +521,9 @@ generation and other stuff.
uninitialized variables do not have the value zero. uninitialized variables do not have the value zero.
Example: Example:
<tscreen><verb>
#pragma bssseg ("MyBSS") #pragma bssseg ("MyBSS")
</verb></tscreen>
<tag><tt>#pragma codeseg (&lt;name&gt;)</tt></tag> <tag><tt>#pragma codeseg (&lt;name&gt;)</tt></tag>
@ -533,8 +537,9 @@ generation and other stuff.
configuration file. configuration file.
Example: Example:
<tscreen><verb>
#pragma bssseg ("MyCODE") #pragma bssseg ("MyCODE")
</verb></tscreen>
<tag><tt>#pragma dataseg (&lt;name&gt;)</tt></tag> <tag><tt>#pragma dataseg (&lt;name&gt;)</tt></tag>
@ -548,8 +553,9 @@ generation and other stuff.
configuration file. configuration file.
Example: Example:
<tscreen><verb>
#pragma bssseg ("MyDATA") #pragma bssseg ("MyDATA")
</verb></tscreen>
<tag><tt>#pragma rodataseg (&lt;name&gt;)</tt></tag> <tag><tt>#pragma rodataseg (&lt;name&gt;)</tt></tag>
@ -563,8 +569,9 @@ generation and other stuff.
configuration file. configuration file.
Example: Example:
<tscreen><verb>
#pragma bssseg ("MyRODATA") #pragma bssseg ("MyRODATA")
</verb></tscreen>
<tag><tt>#pragma regvaraddr (&lt;const int&gt;)</tt></tag> <tag><tt>#pragma regvaraddr (&lt;const int&gt;)</tt></tag>
@ -582,10 +589,11 @@ generation and other stuff.
register variables. So be careful with this #pragma. register variables. So be careful with this #pragma.
Example: Example:
<tscreen><verb>
#pragma regvaraddr(1) /* Allow taking the address #pragma regvaraddr(1) /* Allow taking the address
* of register variables * of register variables
*/ */
</verb></tscreen>
<tag><tt>#pragma signedchars (&lt;const int&gt;)</tt></tag> <tag><tt>#pragma signedchars (&lt;const int&gt;)</tt></tag>
@ -593,15 +601,16 @@ generation and other stuff.
Changed the signedness of the default character type. If the argument Changed the signedness of the default character type. If the argument
is not zero, default characters are signed, otherwise characters are is not zero, default characters are signed, otherwise characters are
unsigned. The compiler default is to make characters unsigned since this unsigned. The compiler default is to make characters unsigned since this
creates a lot better code. creates a lot better code. This default may be overridden by the
<tt/--signed-chars/ command line option.
<tag><tt>#pragma staticlocals (&lt;const int&gt;)</tt></tag> <tag><tt>#pragma staticlocals (&lt;const int&gt;)</tt></tag>
Use variables in the bss segment instead of variables on the stack. This Use variables in the bss segment instead of variables on the stack. This
pragma changes the default set by the compiler option -Cl. If the argument pragma changes the default set by the compiler option <tt/-Cl/. If the
is not zero, local variables are allocated in the BSS segment, leading to argument is not zero, local variables are allocated in the BSS segment,
shorter and in most cases faster, but non-reentrant code. leading to shorter and in most cases faster, but non-reentrant code.
<tag><tt>#pragma zpsym (&lt;name&gt;)</tt></tag> <tag><tt>#pragma zpsym (&lt;name&gt;)</tt></tag>
@ -611,9 +620,10 @@ generation and other stuff.
The compiler will create a matching import declaration for the assembler. The compiler will create a matching import declaration for the assembler.
Example: Example:
<tscreen><verb>
extern int foo; extern int foo;
#pragma zpsym ("foo"); /* foo is in the zeropage */ #pragma zpsym ("foo"); /* foo is in the zeropage */
</verb></tscreen>
</descrip> </descrip>