你好。我用TM4C123G单片机，CCS5进行编译，出现错误如下：
**** Build of configuration Debug for project blinky ****
"D:\\ti\\ccsv5\\utils\\bin\\gmake" -k all
'Building file: ../blinky.c'
'Invoking: ARM Compiler'
"D:/ti/ccsv5/tools/compiler/arm_5.1.1/bin/armcl" -mv7M4 --code_state=16 --float_support=FPv4SPD16 --abi=eabi -me -O2 -g --include_path="D:/ti/ccsv5/tools/compiler/arm_5.1.1/include" --include_path="D:/ti/TivaWare_C_Series-2.0.1.11577" --include_path="D:/ti/ccsv5/tools/compiler/arm_5.1.1/include" --include_path="D:/ti/TivaWare_C_Series-2.0.1.11577" --gcc --define=ccs="ccs" --define=PART_TM4C123GH6PM --diag_warning=225 --display_error_number --diag_wrap=off --gen_func_subsections=on --ual --preproc_with_compile --preproc_dependency="blinky.pp" "../blinky.c"
'Finished building: ../blinky.c'
' '
'Building target: blinky.out'
'Invoking: ARM Linker'
"D:/ti/ccsv5/tools/compiler/arm_5.1.1/bin/armcl" -mv7M4 --code_state=16 --float_support=FPv4SPD16 --abi=eabi -me -O2 -g --gcc --define=ccs="ccs" --define=PART_TM4C123GH6PM --diag_warning=225 --display_error_number --diag_wrap=off --gen_func_subsections=on --ual -z --stack_size=256 -m"blinky_ccs.map" --heap_size=0 -i"D:/ti/ccsv5/tools/compiler/arm_5.1.1/lib" -i"D:/ti/ccsv5/tools/compiler/arm_5.1.1/include" --reread_libs --warn_sections --display_error_number --diag_wrap=off --xml_link_info="blinky_linkInfo.xml" --rom_model -o "blinky.out" "./startup_ccs.obj" "./blinky.obj" "../blinky_ccs.cmd" -l"libc.a"
<Linking>
undefined first referenced
symbol in file
--------- ----------------
GPIOPinRead ./blinky.obj
GPIOPinTypeGPIOInput ./blinky.obj
GPIOPinTypeGPIOOutput ./blinky.obj
GPIOPinWrite ./blinky.obj
SysCtlClockGet ./blinky.obj
SysCtlClockSet ./blinky.obj
SysCtlDelay ./blinky.obj
SysCtlPeripheralEnable ./blinky.obj
error #10234-D: unresolved symbols remain
error #10010: errors encountered during linking; "blinky.out" not built
>> Compilation failure
gmake: *** [blinky.out] Error 1
gmake: Target `all' not remade because of errors.
**** Build Finished ****
头文件GPIO已经包含工程中，为什么会出现这种问题。谢谢
