Hi, recently Thomas Petazzoni reported an issue for the internal toolchain support in Buildroot targeting Blackfin to me. It seem a simple c++ hello world program can't be compiled: cat t.c #include <iostream> int main(void) { std::cout << "hello, world\n"; } ./output/host/usr/bin/bfin-buildroot-linux-uclibc-g++ -o t t.c /home/wbx/buildroot/output/host/usr/lib/gcc/bfin-buildroot-linux-uclibc/6.1.0/../../../../bfin-buildroot-linux-uclibc/bin/ld: t: hidden symbol `___gtdf2' in /home/wbx/buildroot/output/host/usr/lib/gcc/bfin-buildroot-linux-uclibc/6.1.0/libgcc.a(_gt_df.o) is referenced by DSO /home/wbx/buildroot/output/host/usr/lib/gcc/bfin-buildroot-linux-uclibc/6.1.0/../../../../bfin-buildroot-linux-uclibc/bin/ld: final link failed: Bad value collect2: error: ld returned 1 exit status It seems not specific to ___gtdf2, I have seen other symbols in other buildsystems. ./output/host/usr/bin/bfin-buildroot-linux-uclibc-g++ -v Using built-in specs. COLLECT_GCC=/home/wbx/buildroot/output/host/usr/bin/bfin-buildroot-linux-uclibc-g++.br_real COLLECT_LTO_WRAPPER=/home/wbx/buildroot/output/host/usr/libexec/gcc/bfin-buildroot-linux-uclibc/6.1.0/lto-wrapper Target: bfin-buildroot-linux-uclibc Configured with: ./configure --prefix=/home/wbx/buildroot/output/host/usr --sysconfdir=/home/wbx/buildroot/output/host/etc --enable-static --target=bfin-buildroot-linux-uclibc --with-sysroot=/home/wbx/buildroot/output/host/usr/bfin-buildroot-linux-uclibc/sysroot --disable-__cxa_atexit --with-gnu-ld --disable-libssp --disable-multilib --with-gmp=/home/wbx/buildroot/output/host/usr --with-mpfr=/home/wbx/buildroot/output/host/usr --with-pkgversion='Buildroot 2016.08-git-01367-gdf60d48' --with-bugurl=http://bugs.buildroot.net/ --disable-libquadmath --disable-libsanitizer --disable-tls --disable-libmudflap --enable-threads --with-mpc=/home/wbx/buildroot/output/host/usr --without-isl --without-cloog --disable-decimal-float --enable-languages=c,c++ --with-build-time-tools=/home/wbx/buildroot/output/host/usr/bfin-buildroot-linux-uclibc/bin --enable-shared --disable-libgomp Thread model: posix gcc version 6.1.0 (Buildroot 2016.08-git-01367-gdf60d48) binutils 2.26.1, gcc 6.1.0 is used. At least two patches are applied on top of gcc 6.1.0, one for Bug 68468 and one for Bug 71721. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68468 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71721 ADI GNU Toolchain 2014R1 can compile the test program. Does anyone have an idea? best regards Waldemar