Hi , I am compiling bootcode (bootrom.bin) on vxoworks 5.4 - gcc version 3.4.5. The code generated by 3.4.5 is no more assumes the first function of a C file as the starting Address of the compiled code. I think this is because of -funit-at-a-time which is enabled by default by O2 option. But the vxWorks compilation puts un-compressed version of bootrom.bin into Rom Address and puts compressed image into Ram address. When jumping from rom to ram, we jump based on Absolute address. So the earlier code .......... absEntry = (FUNCPTR) (RAM_DST_ADDRESS) absEntry(..) where as RAM_DST_ADDRESS should have the function "compressedEntry" associated with it. And this function used to be the first function in the file bootConfig.c Due to -funit-at-a-time, compressedEntry is no more the first function of bootConfig.o So the loader command "...-e compressedEntry -Ttext (RAM_DST_ADDRESS) places bootConfig.o in RAM_DST_ADDRESS, but the first function is placed after some offset. I used -fno-unit-at-a-time , and it was fine. But just concerned about the throughput of the code generated. Is there any other way to deal with this problem ? thanks in advance Aparna
