[B2-devel] dyngen.c patch for mach-o x86_64

[Jean-Pierre <cho...@fr...>]

Hi,

I continue my monologue...

Here's a more complete patch for dyngen.c.
This version correctly deals with mach-o 64-bit object files built by  
gcc-4.2.1 as well as gcc-4.0.

Note that there's actually a bug in Apple's gcc 4.2.1 which seems to  
ignore the -fomit-frame-pointer for 64 bit x86_64 code.
i.e.:

With gcc-4.0, the following tiny source code:

	// tst.cpp
	register unsigned int *A0 asm("ebx");
	
	void op_mov_ad_A0_im(void)
	{
		asm volatile ("movabsq $___op_A0,%0" : "=r" (A0));
	}

compiled using:

	gcc-4.0 -arch x86_64 -fomit-frame-pointer -c tst.cpp

produces this otool result:

	tst.o:
	(__TEXT,__text) section
	__Z15op_mov_ad_A0_imv:
	0000000000000000	movq	$0x0000000000000000,%rbx
	000000000000000a	ret

But when compiled using gcc-4.2.1 from Snow Leopard:

	gcc -arch x86_64 -fomit-frame-pointer -c tst.cpp

produces this otool result:

	tst.o:
	(__TEXT,__text) section
	__Z15op_mov_ad_A0_imv:
	0000000000000000	pushq	%rbx
	0000000000000001	movq	$0x0000000000000000,%rbx
	000000000000000b	popq	%rbx
	000000000000000c	ret

my gcc version: i686-apple-darwin10-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc.  
build 5646) (dot 1)

I filed a bug at Apple about this.

I also have a few other patches available:
One for clip_macosx.cpp to deal with ne new Pasteboard functions since  
GetCurrentScrap/PutScrapFlavor etc.. have disappeared in Snow  
Leopard's APIs.
One for video_blit.cpp to accept the new GBRA format returned by the  
latest SLD-1.2.14, and a patch for this SDL to remove a memory leak  
(bug filed at libsdl.org).
Let me know if you want them or if you don't care...

Regards,

  - Jean-Pierre.