https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66343
Simon Lindholm <simon.lindholm10 at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |simon.lindholm10 at gmail dot com --- Comment #3 from Simon Lindholm <simon.lindholm10 at gmail dot com> --- Seems to happen when both source and precompiled header files contain a division: $ echo "void div1(int a, int b) { a / b; }" >header.h $ echo "void div2(int a, int b) { a / b; }" >src.cpp $ g++ -fsanitize=undefined header.h $ g++ -fsanitize=undefined -include header.h src.cpp /tmp/ccoYhDz6.s: Assembler messages: /tmp/ccoYhDz6.s:69: Error: symbol `.Lubsan_data0' is already defined (reproduced on gcc 6.1.1)