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Cant compile using g++ -O2 or -O3

Hi

I can run my code using O mode but when I try to use the compilers advanced optimization settings I get whole load of funny errors. Any suggestions?

Thanks

Niall

This isn't all of the errors, just the first few!
 
 
pclxb10>make
g++ -o2 csvdemo main.cpp csvparser.cpp
csvdemo: In function `_start':
(.text+0x0): multiple definition of `_start'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crt1.o:(.text+0x0): first defined here
csvdemo:(.rodata+0x0): multiple definition of `_fp_hw'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crt1.o:(.rodata+0x0): first defined here
csvdemo: In function `_fini':
(.fini+0x0): multiple definition of `_fini'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crti.o:(.fini+0x0): first defined here
csvdemo:(.rodata+0x4): multiple definition of `_IO_stdin_used'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crt1.o:(.rodata.cst4+0x0): first defined here
csvdemo: In function `__data_start':
(.data+0x0): multiple definition of `__data_start'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crt1.o:(.data+0x0): first defined here
csvdemo:(.rodata+0x8): multiple definition of `__dso_handle'
/usr/lib/gcc/i386-redhat-linux/4.1.2/crtbegin.o:(.rodata+0x0): first defined here
csvdemo: In function `_init':

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Infinity08

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Infinity08

The reason for all those errors, is because the compiler compiled the two .cpp files, and then the linker tried to link them together with the csvdemo executable that was there from an earlier build. Obviously these contain the exact same symbols.