https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114441
--- Comment #3 from Yang Wang <njuwy at smail dot nju.edu.cn> --- (In reply to Andrew Pinski from comment #1) > This is not a GCC bug, > > You need to use -mcmodel=large if you have huge statically allocated arrays. > > The default -mcmodel=medium does not support more than 2GB size arrays > > See > https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/x86-Options.html#index- > mcmodel_003dlarge-3 Thanks for your reply! Indeed, the compilation was successful when either the -mcmodel=medium or -mcmodel=large was enabled. However, I'm still curious why it can be compiled successfully at the -O3 optimization level when the default -mcmodel=small is enabled? As far as I know, the -O3 optimization level is the highest. root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=medium -O0 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=medium -O3 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=medium -O1 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=medium -O2 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=medium -Os root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=small -O0 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=small -O3 root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=small -O1 /tmp/ccdtPXUH.o: In function `c()': 222.cpp:(.text+0xd): relocation truncated to fit: R_X86_64_32S against symbol `a' defined in .bss section in /tmp/ccdtPXUH.o collect2: error: ld returned 1 exit status root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=small -O2 /tmp/ccbjzODN.o: In function `c()': 222.cpp:(.text+0x13): relocation truncated to fit: R_X86_64_32S against symbol `a' defined in .bss section in /tmp/ccbjzODN.o collect2: error: ld returned 1 exit status root@ubuntu:~/test/111# /root/software/IP-gcc/gcc-trunk/bin/g++ 222.cpp -o test -w -mcmodel=small -Os /tmp/ccUUdbLp.o: In function `c()': 222.cpp:(.text+0x7): relocation truncated to fit: R_X86_64_32S against symbol `a' defined in .bss section in /tmp/ccUUdbLp.o collect2: error: ld returned 1 exit status
