http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57484
--- Comment #8 from Charles L. Wilcox <zxClhzAApX1EdJwQANqrjLERmFeURQVy at cynd dot net> --- FWIW, I tried this with g++ 4.8 on a 32-bit only system I have; it still produces erroneous sNaN values there: $ g++-4.8 -v Using built-in specs. COLLECT_GCC=g++-4.8 COLLECT_LTO_WRAPPER=/usr/lib/gcc/i486-linux-gnu/4.8/lto-wrapper Target: i486-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Debian 4.8.1-1' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs --enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.8 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.8-i386/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.8-i386 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.8-i386 --with-arch-directory=i386 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-targets=all --enable-multiarch --with-arch-32=i586 --with-multilib-list=m32,m64,mx32 --with-tune=generic --enable-checking=release --build=i486-linux-gnu --host=i486-linux-gnu --target=i486-linux-gnu Thread model: posix gcc version 4.8.1 (Debian 4.8.1-1) $ g++-4.8 -Wall -Wextra test-signaling-nan.cpp $ ./a.out Signaling NaN for type "f" in hex is "7fe00000". Signaling NaN's signaling-bit status for type "f" is set to "true". Quiet NaN for type "f" in hex is "7fc00000". Quiet NaN's signaling-bit status for type "f" is set to "true". Signaling NaN for type "d" in hex is "7ffc000000000000". Signaling NaN's signaling-bit status for type "d" is set to "true". Quiet NaN for type "d" in hex is "7ff8000000000000". Quiet NaN's signaling-bit status for type "d" is set to "true".
