Package: libc6-dev Version: 2.7-18 Severity: normal /usr/include/ieee754.h includes unions to break down the different floating-point types into their component bits. Unfortunately, this file contains a 96-bit version for long double, whilst amd64 uses a 128-bit long double. Thus, the problem does not exist when using -m32, but does for 64-bit programs. A sample program is attached; it successfully runs with -m32, but fails without it. This problem does not occur on sparc. -- System Information: Debian Release: 5.0 APT prefers unstable APT policy: (500, 'unstable'), (1, 'experimental') Architecture: amd64 (x86_64) Kernel: Linux 2.6.28-1-amd64 (SMP w/2 CPU cores) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8) Shell: /bin/sh linked to /bin/bash Versions of packages libc6-dev depends on: ii l 2.7-18 GNU C Library: Shared libraries ii l 2.6.28-1~experimental.1~snapshot.12762 Linux support headers for userspac Versions of packages libc6-dev recommends: ii gcc [c-compiler] 4:4.3.2-3 The GNU C compiler ii gcc-3.4 [c-compiler] 3.4.6-9 The GNU C compiler ii gcc-4.1 [c-compiler] 4.1.2-25 The GNU C compiler ii gcc-4.2 [c-compiler] 4.2.4-6 The GNU C compiler ii gcc-4.3 [c-compiler] 4.3.3-3 The GNU C compiler Versions of packages libc6-dev suggests: pn glibc-doc <none> (no description available) ii manpages-dev 3.17-1 Manual pages about using GNU/Linux -- no debconf information -- brian m. carlson / brian with sandals: Houston, Texas, US +1 713 440 7475 | http://crustytoothpaste.ath.cx/~bmc | My opinion only troff on top of XML: http://crustytoothpaste.ath.cx/~bmc/code/thwack OpenPGP: RSA v4 4096b 88AC E9B2 9196 305B A994 7552 F1BA 225C 0223 B187
#include <stddef.h>
#include <stdio.h>
#include <ieee754.h>
int main(void)
{
union ieee854_long_double ild;
const size_t ld = sizeof(long double);
const size_t ilds = sizeof(ild.ieee);
printf("%d %d %s\n", ld, ilds, (ld == ilds ? "ok" : "fail"));
return ld != ilds;
}
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