From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <389EE09A.571A6C26@denise.shiny.it> Date: Mon, 07 Feb 2000 16:11:22 +0100 From: Giuliano Pochini MIME-Version: 1.0 To: Adrian Cox CC: LinuxPPC-Dev , Debian PowerPC Subject: Re: Altivec and binary compatibility References: <389AAA06.CBCDB19A@agelectronics.co.uk> Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: > Altivec raises an interesting question of binary compatibility, in the > area of C++ exceptions and C setjmp/longjmp. > > As the jmp_buf is a different size in Altivec and non-Altivec code Because with Altivec we need to save V registers, right ? Well, I suppose intel developers had the same problem with P-III "vector" unit. How did they solve the problem ? > it is not possible to jump or pass exceptions between the two. > This is a problem, because: > 1) Now would not be a good time to change the size of a jmp_buf. > 2) We do not need two incompatible 32-bit PowerPC ABIs under Linux. > 2a) Most libraries installed by a distribution will be non-Altivec code, > to avoid having both G[123] and G4 binary variants of the distribution. I agree. > To add to the problem, throwing exceptions on an error is just what a > modern C++ library is supposed to do. Throwing or catching an exception > in Altivec code will produce sequences that cannot execute on a G3 Why ?? (sorry for my ignorance...) Bye. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/