Bad case

Good case:

..
nios2-elf-ranlib ./libgcov.a
`if [ -f /WRKOBJDIR/cross/nios2-gcc/work/gcc/bison/bison ] ;
   then echo /WRKOBJDIR/cross/nios2-gcc/work/gcc/bison/bison -L
  /WRKOBJDIR/cross/nios2-gcc/work/gcc/bison/ ; else echo bison ; fi` 
  -o c-parse.c c-parse.y
bison: not found
Makefile:1334: recipe for target 'c-parse.c' failed
gmake[3]: [c-parse.c] Error 127 (ignored)

To fix this problem, bison should NOT be listed in USE_TOOLS. If it is listed, make will execute bison, and c-parse.y is generated. The fact is c-parse.y is already there and should not be generated.