Bug 14068

Summary:	Split top-level config.h.in into machine dependent and machine independent pieces.
Product:	glibc	Reporter:	Carlos O'Donell <carlos_odonell>
Component:	build	Assignee:	Carlos O'Donell <carlos>
Status:	NEW ---
Severity:	normal	CC:	carlos, drepper.fsp, roland
Priority:	P2	Flags:	fweimer: security-
Version:	unspecified
Target Milestone:	---
Host:		Target:
Build:		Last reconfirmed:

Description Carlos O'Donell 2012-05-06 23:48:30 UTC

At present the glibc sources have one top-level config.h.in file.

The config.h.in file contains several definitions for x86, x86_64, Power, and ARM.

Logically speaking this file should contain only machine independent definitions.

Instead each machine should have a config.h.in fragment that is aggregated together with the top-level config.h.in to produce a final config.h.

At present each machine needs to add defines to the top-level config.h.in.

Comment 1 jsm-csl@polyomino.org.uk 2012-05-07 10:23:05 UTC

On Sun, 6 May 2012, carlos_odonell at mentor dot com wrote:

> The config.h.in file contains several definitions for x86, x86_64, Power, and
> ARM.

And SPARC (HAVE_AS_VIS3_SUPPORT, HAVE_GCC_GOTDATA).  And Linux-specific 
(__LINUX_KERNEL_VERSION).  And some Mach-specific defines 
(HAVE_HOST_PAGE_SIZE, HAVE_I386_IO_PERM_MODIFY, HAVE_I386_SET_GDT, 
HAVE_MIG_RETCODE - the last of these isn't used anywhere and for the 
middle two, only used in sysdeps/mach/hurd/i386/, I'd have thought glibc 
could just require the preferred answer to the test rather than 
conditioning things).  And one of the Power defines (BROKEN_PPC_ASM_CR0) 
actually has its configure test directly in the toplevel configure.in.

Comment 2 Carlos O'Donell 2012-05-07 20:12:51 UTC

As always we should look to see if any of these checks are still valid.

For example we could use `-ansi' instead of `-undef' in the implicit rule to allow HAVE_ARM_PCS_VFP to go away and become simply %ifdef __ARM_PCS_VFP in ARM's shlib-versions.