minix/include/minix/compiler.h
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

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2 KiB
C

/* Definitions for compiler-specific features. */
#ifndef _MINIX_COMPILER_H
#define _MINIX_COMPILER_H
/*===========================================================================*
* Compiler overrides *
*===========================================================================*/
/* ACK */
#ifdef __ACK__
#include <minix/compiler-ack.h>
#endif
/*===========================================================================*
* Default values *
*===========================================================================*/
/*
* cdecl calling convention expects the callee to pop the hidden pointer on
* struct return. For example, GCC and LLVM comply with this (tested on IA32).
*/
#ifndef BYTES_TO_POP_ON_STRUCT_RETURN
#define BYTES_TO_POP_ON_STRUCT_RETURN $4
#endif
/*
* cdecl calling convention requires to push arguments on the stack in a
* reverse order to easily support variadic arguments. Thus, instead of
* using the proper stdarg.h macros (that nowadays are
* compiler-dependant), it may be tempting to directly take the address of
* the last argument and considering it as the start of an array. This is
* a shortcut that avoid looping to get all the arguments as the CPU
* already pushed them on the stack before the call to the function.
*
* Unfortunately, such an assumption is strictly compiler-dependant and
* compilers are free to move the last argument on the stack, as a local
* variable, and return the address of the location where the argument was
* stored, if asked for. This will break things as the rest of the array's
* argument are stored elsewhere (typically, a couple of words above the
* location where the argument was stored).
*
* Conclusion: if unsure on what the compiler may do, do not make any
* assumption and use the right (typically compiler-dependant) macros.
*/
#ifndef FUNC_ARGS_ARRAY
#define FUNC_ARGS_ARRAY 0
#endif
#endif /* _MINIX_COMPILER_H */