tree 63072a0f058197ade09040ccdd1c6e2e6963d8a7
parent 3e431ba8c9de8d676f1b968cbb7b1e03d0ca5753
author Pali Rohár <pali.rohar@gmail.com> 1752782921 +0200
committer Martin Storsjö <martin@martin.st> 1753966961 +0300

crt: Fix LTO -Ofast compilation

When mingw-w64 is compiled with LTO support (-flto and -ffat-lto-objects in
CFLAGS and LDFLAGS) then compiling any application with -Ofast fails.

Calling "gcc -flto -Ofast" throws fatal error:

    `___main' referenced in section `.text.startup' of /tmp/ccXtREge.ltrans0.ltrans.o: defined in discarded section `.text' of lib32_libmingw32_a-gccmain.o (symbol from plugin)
    collect2: error: ld returned 1 exit status

With -O2 or other level there is no error at all.

It looks like that function __main from file mingw-w64-crt/crt/gccmain.c is
somehow automatically discarded by gcc / ld LTO compiler when using -Ofast.

Fix this problem by manually adding __attribute__((used)).

Signed-off-by: Martin Storsjö <martin@martin.st>