In my embedded project I compile `amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.c` in this way:
/opt/gcc-arm-none-eabi-8-2019-q3-update/bin/arm-none-eabi-gcc \ -std=gnu11 \ -mcpu=cortex-m7 \ -mthumb \ -mapcs \ -mfloat-abi=hard \ -mfpu=fpv5-d16 \ -fno-common \ -fno-math-errno \ -fsingle-precision-constant \ -fno-trapping-math \ -fno-signaling-nans \ -fno-builtin \ -fstrict-aliasing \ -fstack-usage \ -Wstack-usage=300 \ -DCPU_MIMXRT1051DVL6B \ -D__FREERTOS__=1 \ -DFSL_RTOS_FREE_RTOS \ -DFSL_FEATURE_PHYKSZ8081_USE_RMII50M_MODE \ -D__MCUXPRESSO \ -D__USE_CMSIS \ -DARM_MATH_CM7 \ -D__NEWLIB__ \ -DDEBUG=0 \ -IDSP/source/ \ -Iamazon-freertos/lib/FreeRTOS-Plus-TCP/ \ -Iamazon-freertos/lib/FreeRTOS-Plus-TCP/portable/BufferManagement/ \ -Iamazon-freertos/lib/FreeRTOS-Plus-TCP/portable/NetworkInterface/imxrt105x/ \ -Iamazon-freertos/lib/FreeRTOS/ \ -Iamazon-freertos/lib/include/ \ -Iamazon-freertos/lib/FreeRTOS/portable/GCC/ARM_CM4F/ \ -Iamazon-freertos/lib/FreeRTOS/portable/MemMang/ \ -Og \ -g3 \ -Wall \ -ffunction-sections \ -fdata-sections \ -c \ -MMD \ -MP \ -Werror \ -D"ARCPRINTF( ... )=(void)0" \ --specs=nano.specs \ -Wa,-anhlmsd=build/DSP/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.lst \ -o build/DSP/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.o amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.c
I have `ipconfigUSE_TCP` set to 1 in `amazon-freertos/lib/FreeRTOS-Plus-TCP/include/FreeRTOSIPConfig.h``FreeRTOS_Sockets.c` declares `xBoundUDPSocketsList` and `xBoundTCPSocketsList`
/* The list that contains mappings between sockets and port numbers. Accesses to this list must be protected by critical sections of one kind or another. */ List_t xBoundUDPSocketsList; #if ipconfigUSE_TCP == 1 List_t xBoundTCPSocketsList; #endif /* ipconfigUSE_TCP == 1 */
Once I have my elf executable linked, run this command:
$ /opt/gcc-arm-none-eabi-8-2019-q3-update/bin/arm-none-eabi-nm -a -l -n -t x --print-size image/DSP.elf | grep -E '^[[:xdigit:]]{8} [[:xdigit:]]{8} B' | grep SocketsList 2001ac7c 00000014 B xBoundTCPSocketsList 2001ac90 00000014 B xBoundUDPSocketsList /home/max/Lavori/4202/src/repos/toremove/FW/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.c:162
Both symbols exist in the executable, but one (`xBoundTCPSocketsList`) does not seem to belong to any .c source.Both appear in the map file:
$ grep -n -A 1 -E 'xBoundTCPSocketsList|xBoundUDPSocketsList' image/DSP.map 61974: .bss.xBoundTCPSocketsList 61975- 0x000000002001ac7c 0x14 ./build/DSP/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.o 61976: 0x000000002001ac7c xBoundTCPSocketsList 61977: .bss.xBoundUDPSocketsList 61978- 0x000000002001ac90 0x14 ./build/DSP/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.o 61979: 0x000000002001ac90 xBoundUDPSocketsList
Even addr2line fails:
$ arm-none-eabi-addr2line -a -e image/DSP.elf 2001ac7c 2001ac90 0x2001ac7c ??:0 0x2001ac90 /home/max/Lavori/4202/src/repos/toremove/FW/amazon-freertos/lib/FreeRTOS-Plus-TCP/FreeRTOS_Sockets.c:162
even the `FreeRTOS_Sockets.lst` doesn't tell me anything more:
7337 .global xBoundTCPSocketsList 7338 .global xBoundUDPSocketsList 7339 .section .bss.xBoundTCPSocketsList,"aw",%nobits 7340 .align 2 7341 .set .LANCHOR2,. + 0 7344 xBoundTCPSocketsList: 7345 0000 00000000 .space 20 7345 00000000 7345 00000000 7345 00000000 7345 00000000 7346 .section .bss.xBoundUDPSocketsList,"aw",%nobits 7347 .align 2 7348 .set .LANCHOR1,. + 0 7351 xBoundUDPSocketsList: 7352 0000 00000000 .space 20 7352 00000000 7352 00000000 7352 00000000 7352 00000000
There are many other symbols present in the executable but which do not seem to be associated with any .c source file.Why this behavior? What changes between the two symbols `xBoundTCPSocketsList` and `xBoundUDPSocketsList`? Am I getting it wrong or omitting some debugging parameters when compiling? How do I get either nm or some other way to get the .c source where a symbol is declared?
best regards
Max