[U-Boot-Users] STD_C and STDC_

Hello! Everyone,I was reading the U-boot of the mpc8260 in recent months. And I was a freshman. Yesterday,When I was reading the U-boot1.1.4\include\malloc.h, I was puzzled by the ln223 and the ln224 (#ifndef _STD_C #ifdef _STDC_). I don't understand the differeces between the "_STD_C" and "_STDC_".Could anyone can help me? Thank you very much!

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