a c2h problem

i use altera ep2c35 board. when i used c2h to accelarate the functions,i met a problem like this:

c:/altera/kits/nios2_60/components/altera_avalon_c_hardware_accelerator/c_declaration.pm 113 CALLED (c_code_block::user_error)

c:/altera/kits/nios2_60/components/altera_avalon_c_hardware_accelerator/c_code_block.pm 6083 CALLED (c_code_block::user_message) WHERE

'::C2H ERROR: copysign already declared

at file: , line:' OCCURRED on c:/altera/kits/nios2_60/components/altera_avalon_c_hardware_accelerator/c_code_block.pm 6136

so i can't pass through the build!

someone can help me!

thanks!