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          printf("unexpected\n");
          break;
    @}
@end example

@cindex aligned attribute
@cindex packed attribute
@cindex section attribute
@cindex unused attribute
@cindex cdecl attribute
@cindex stdcall attribute
@cindex regparm attribute
@cindex dllexport attribute

@item The keyword @code{__attribute__} is handled to specify variable or
function attributes. The following attributes are supported:
  @itemize

  @item @code{aligned(n)}: align a variable or a structure field to n bytes
(must be a power of two).

  @item @code{packed}: force alignment of a variable or a structure field to
  1.

  @item @code{section(name)}: generate function or data in assembly section
name (name is a string containing the section name) instead of the default
section.

  @item @code{unused}: specify that the variable or the function is unused.

  @item @code{cdecl}: use standard C calling convention (default).

  @item @code{stdcall}: use Pascal-like calling convention.

  @item @code{regparm(n)}: use fast i386 calling convention. @var{n} must be
between 1 and 3. The first @var{n} function parameters are respectively put in
registers @code{%eax}, @code{%edx} and @code{%ecx}.

  @item @code{dllexport}: export function from dll/executable (win32 only)

  @end itemize

Here are some examples:
@example
    int a __attribute__ ((aligned(8), section(".mysection")));
@end example

@noindent
align variable @code{a} to 8 bytes and put it in section @code{.mysection}.

@example
    int my_add(int a, int b) __attribute__ ((section(".mycodesection"))) 
    @{
        return a + b;
    @}
@end example

@noindent
generate function @code{my_add} in section @code{.mycodesection}.

@item GNU style variadic macros:
@example
    #define dprintf(fmt, args@dots{}) printf(fmt, ## args)

    dprintf("no arg\n");
    dprintf("one arg %d\n", 1);
@end example

@item @code{__FUNCTION__} is interpreted as C99 @code{__func__} 
(so it has not exactly the same semantics as string literal GNUC
where it is a string literal).

@item The @code{__alignof__} keyword can be used as @code{sizeof} 
to get the alignment of a type or an expression.

@item The @code{typeof(x)} returns the type of @code{x}. 
@code{x} is an expression or a type.

@item Computed gotos: @code{&&label} returns a pointer of type 
@code{void *} on the goto label @code{label}. @code{goto *expr} can be
used to jump on the pointer resulting from @code{expr}.

@item Inline assembly with asm instruction:
@cindex inline assembly
@cindex assembly, inline
@cindex __asm__
@example
static inline void * my_memcpy(void * to, const void * from, size_t n)
@{
int d0, d1, d2;
__asm__ __volatile__(
        "rep ; movsl\n\t"
        "testb $2,%b4\n\t"
        "je 1f\n\t"
        "movsw\n"
        "1:\ttestb $1,%b4\n\t"
        "je 2f\n\t"
        "movsb\n"
        "2:"
        : "=&c" (d0), "=&D" (d1), "=&S" (d2)
        :"0" (n/4), "q" (n),"1" ((long) to),"2" ((long) from)
        : "memory");
return (to);
@}
@end example

@noindent
@cindex gas
TCC includes its own x86 inline assembler with a @code{gas}-like (GNU
assembler) syntax. No intermediate files are generated. GCC 3.x named
operands are supported.

@item @code{__builtin_types_compatible_p()} and @code{__builtin_constant_p()} 
are supported.

@item @code{#pragma pack} is supported for win32 compatibility.

@end itemize

@section TinyCC extensions