------- Comment #9 from exploringbinary at gmail dot com 2010-06-04 01:31 ------- I discovered two other examples of incorrect rounding in gcc:
1) 0.500000000000000166533453693773481063544750213623046875 2) 1.50000000000000011102230246251565404236316680908203125 These are both halfway cases. Example 1 has bit 53 equal to 1, so it should round up; gcc rounds down. Example 2 has bit 53 equal to 0, so it should round down; gcc rounds up. I've written an article describing these examples in more detail: http://www.exploringbinary.com/incorrectly-rounded-conversions-in-gcc-and-glibc/ . BTW, why doesn't gcc use David Gay's dtoa.c (http://www.netlib.org/fp/dtoa.c) for correct rounding? -- exploringbinary at gmail dot com changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |exploringbinary at gmail dot | |com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21718
