编译C库时的警告

Question

I am trying to compile a C library and I am getting a loy of warning while doing it. Though the compiled library is working properly, I am still a bit apprehensive about the warnings. I googled all the warnings, but the relevant search results are hard to come by.

The warnings are:

main(){printf("osx%d", (int) (sizeof(void *)*8));} ^~~~ 1 warning generated. clang: warning: argument unused during compilation: '-s'

This warning is in the shell script that I used to compile the libraries. Could someone tell me what the -'s' flag is and how I can remove this warning?

Next warning:

warning: unknown warning option '-Wno-long-double'; did you mean '-Wno-long-long'? [-Wunknown-warning-option]

and the next one, /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: fortify.o has no symbols clang: warning: argument unused during compilation: '-s'

Anyway to silence these warning?

Answer 1

Look at the manual of gcc for details of what each option should do.

AFAICT, clang not accepting those flags does not lead to any failure of the built executable.

Excerpt:

• -s: Remove all symbol table and relocation information from the executable. (linker)
• -Wno-long-double: Looks like someone wants to disable use of long double . Cannot find it for newest GCC. Chances are the code does not contain such anyway.