$ cat b.cc
#include <iostream>
using namespace std;
void init(long double& n, int k) {
n = k;
}
int main() {
long double n;
init(n, -2);
cout << n << endl;
}
$ g++ b.cc ; ./a.out
-2
$ g++ -m64 b.cc ; ./a.out
4.29497e+09
$ g++ -O1 -m64 b.cc ; ./a.out
-2
$ g++ -O2 -m64 b.cc ; ./a.out
-2
$ g++ -O3 -m64 b.cc ; ./a.out
-2
$ g++ -mhard-quad-float -m64 b.cc ; ./a.out
-2
$ gcc -v
Using built-in specs.
Target: sparc-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 4.3.1-2'
--with-bugurl=file:///usr/share/doc/gcc-4.3/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.3
--program-suffix=-4.3 --enable-clocale=gnu --enable-libstdcxx-debug
--enable-objc-gc --enable-mpfr --with-cpu=v8 --with-long-double-128
--enable-checking=release --build=sparc-linux-gnu --host=sparc-linux-gnu
--target=sparc-linux-gnu
Thread model: posix
gcc version 4.3.1 (Debian 4.3.1-2)
$ cat /proc/cpuinfo
cpu : TI UltraSparc II (BlackBird)
fpu : UltraSparc II integrated FPU
prom : OBP 3.16.1 1999/04/19 07:55
type : sun4u
ncpus probed : 2
ncpus active : 2
D$ parity tl1 : 0
I$ parity tl1 : 0
Cpu0ClkTck : 0000000017d78400
Cpu1ClkTck : 0000000017d78400
MMU Type : Spitfire
State:
CPU0: online
CPU1: online
--
Summary: long double is buggy on sparc64
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: bagnara at cs dot unipr dot it
GCC host triplet: sparc64-unknown-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37661
