multibyteMulAdd "is already defined" with -flto=full on i686 #4294
Description
Trying to port btdu to i686 I ran into this. ldc-build-runtime is invoked with --dFlags="-flto=full" and later ldc2 with -flto=full and -static. This happens (but does not happen on x86_64):
/usr/bin/i686-linux-gnu-gcc btdu-static-i686.o -static -o btdu-static-i686 -Wl,-plugin,/tmp/ldc2-1.30.0-linux-x86_64/lib/LLVMgold-ldc.so -Wl,-plugin-opt=mcpu=pentium4 -Wl,-plugin-opt=O3 -Wl,-plugin-opt=-function-sections -Wl,-plugin-opt=-data-sections -Lrelease -l:libtermcap.a -l:libncursesw.a -l:libtinfo.a -l:libz.a -L/tmp/ldc-build-runtime.tmp/lib -lphobos2-ldc -ldruntime-ldc -Wl,--gc-sections -lrt -ldl -lpthread -lm -m32
/usr/lib/gcc-cross/i686-linux-gnu/8/../../../../i686-linux-gnu/bin/ld: error: LLVM gold plugin: <inline asm>:876:1: symbol '.L_D3std8internal4math10biguintx86__T15multibyteMulAddVai43ZQxFNaNbNfAkxAkkkZk_L1' is already defined
.L_D3std8internal4math10biguintx86__T15multibyteMulAddVai43ZQxFNaNbNfAkxAkkkZk_L1: mull 36(%esp)
^
collect2: error: ld returned 1 exit status
Error: /usr/bin/i686-linux-gnu-gcc failed with status: 1
DOCKER=podman ci/build-docker.sh i686 x86_64 aarch64 58.45s user 12.43s system 77% cpu 1:31.21 total
Let me know if you need a full reproducer.