Bug#987637: fenix FTBFS with gcc 10

[Adrian Bunk]

Source: fenix
Version: 0.92a.dfsg1-12
Severity: serious
Tags: ftbfs bullseye sid

https://tests.reproducible-builds.org/debian/rb-pkg/bullseye/i386/fenix.html

...
gcc  -g -O2 -fdebug-prefix-map=/build/fenix-0.92a.dfsg1=. -fstack-protector-strong -Wformat -Werror=format-security -Wall -fno-strict-aliasing -DUSE_GETTEXT   -Wl,-z,relro -Wl,-z,defs -o fxc main.o main_div.o token.o identifier.o segment.o constants.o strings.o varspace.o procedure.o codeblock.o c_main.o c_data.o c_code.o c_debug.o dcbw.o messages.o error.o sysstub.o typedef.o files.o xctype.o -L/usr/lib/i386-linux-gnu -lSDL -Wl,-Bdynamic -lc -lz -lX11 -lm -ldl
/usr/bin/ld: c_main.o:./fxc/src/c_main.c:185: multiple definition of `debug'; main.o:./fxc/src/main.c:60: first defined here
collect2: error: ld returned 1 exit status
make[4]: *** [Makefile:391: fxc] Error 1