Building sa-exim throws lots of warnings like this one:
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gcc -I/usr/include/exim4 -fPIC -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -fdebug-prefix-map=/dev/shm/EXIM4/sa-exim-4.2.1=. -fstack-protector-strong -Wformat -Werror=format-security -shared -Wl,-z,relro -o sa-exim.so sa-exim.c
sa-exim.c: In function 'savemail':
sa-exim.c:285:92: warning: format '%d' expects argument of type 'int', but argument 5 has type 'long unsigned int' [-Wformat=]
285 | log_write(0, LOG_MAIN, "SA: Debug9: Archive body write starts: writing up to %d bytes in %d byte blocks", SAmaxarchivebody, sizeof(buffera));
| ~^ ~~~~~~~~~~~~~~~
| | |
| int long unsigned int
| %ld
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cu Andreas