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GCC fails with -O2 for own Target

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I have ported the GCC (v4.5.3) to a new target (32-bit RISC processor). So far everything went fine. I wrote my own little C-Lib with basic input output and tested it worked. Until today I never actually tried optimization passes (maybe that was the mistake that lead to this)
Anyway:
During porting and building Newlib I ran into an error that I tracked down to the following code:

unsigned char hexdig[256];

static void htinit ( unsigned char *h , unsigned char *s , int inc)
{
 int i, j;
 for(i = 0; (j = s[i]) !=0; i++)
 h[j] = i + inc;
}

void
hexdig_init ()
{
 htinit(hexdig, (unsigned char *) "0123456789", 0x10);
 htinit(hexdig, (unsigned char *) "abcdef", 0x10 + 10);
 htinit(hexdig, (unsigned char *) "ABCDEF", 0x10 + 10);
}

Compiling this code without optimization works like a charm, however compiling it with -O2 leads to the following error:
test1.c: In function 'hexdig_init':
test1.c:11:1: internal compiler error: in gen_lowpart_general, at rtlhooks.c:59

Tried with:
eco32-gcc -O2 -S test1.c

My question in short is:
Could this be a targe- backend-error or just some configuration I have missed while building GCC?
Any pointers into the right direction are welcome.

posted Jul 25, 2013 by anonymous

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1 Answer

0 votes

It is most likely an error in your backend. The first step is to break out the debugger and find out why that function is being called with something that is not a MEM. You may want to look at http://gcc.gnu.org/wiki/DebuggingGCC

answer Jul 25, 2013 by anonymous
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