https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81412
Bug ID: 81412 Summary: roundq Product: gcc Version: 7.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libquadmath Assignee: unassigned at gcc dot gnu.org Reporter: fjwyhzb at hotmail dot com Target Milestone: --- Created attachment 41732 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41732&action=edit roundq-bug.i $ cat roundq-bug.c #include <stdio.h> #include <quadmath.h> int main(void) { double x = 2147483648.7; printf("roundq(%.1f) = %.1f\n", x, (double)roundq(x)); } $ gcc -save-temps -Wall -Wextra roundq-bug.c -lquadmath $ ./a.out roundq(2147483648.7) = 2147483648.7 $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/7.1.1/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared --enable-threads=posix --enable-libmpx --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --disable-multilib --disable-werror --enable-checking=release Thread model: posix gcc version 7.1.1 20170621 (GCC)