CODEWITHSUNDEEP
cembeddedobjdumpbinutilsnm
mohammadsdtmnd
mohammadsdtmnd

Reputation: 390

`nm` and `objdump` unknown dollar signed symbol

Th nm source.o gives unknown symbols:

F:\STM32CubeIDE\LMS\ANC_fxlms_v1\Debug\Core\Src>nm FX_LMS.o
00000000 b $d
00000298 t $d
00000000 b $d
000000b4 t $d
00000000 b $d
00000544 t $d
00000024 t $d
00000000 b $d
000002b0 t $d
00000000 d $d
000001f8 t $d
00000000 b $d
00000178 t $d
00000000 b $d
00000000 b $d
00000000 b $d
000000f0 t $d
00000000 b $d
00000058 t $d
00000000 b $d
00000000 b $d
00000000 b $d
00000000 b $d
00000000 b $d
00000050 t $d
00000000 b $d
000005ec t $d
00000000 b $d
00000664 t $d
00000000 b $d
00000000 b $d
0000003c t $d
00000000 t $t
.
.
.
00000000 t $t
00000000 t $t
         U ADC_DMAError
         U ADC_Enable
00000001 T ADC_Start_DMA_double
0000010c d aecho.0
.
.
.

I want to know the meaning of the $d and $t symbol. What is that? What is a reference that explain those? This is the compiled C source from eclipse (STM32cubeIDE on Windows 10 64-bit).

The maybe important build commands copied from eclipse console:

21:04:01 **** Incremental Build of configuration Debug for project ANC_fxlms_v1 ****
make -j8 all 
arm-none-eabi-gcc "../Core/Src/FX_LMS.c" -mcpu=cortex-m7 -std=gnu11 -g3 -DDEBUG -DARM_MATH_CM7 -DUSE_HAL_DRIVER -DSTM32H743xx -c -I../Core/Inc -I"F:/STM32CubeIDE/LMS/ANC_fxlms_v1/Core/Inc/drv" -I"F:/STM32CubeIDE/LMS/ANC_fxlms_v1/Drivers/CMSIS/DSP/Include" -I../Drivers/STM32H7xx_HAL_Driver/Inc -I../Drivers/STM32H7xx_HAL_Driver/Inc/Legacy -I../Drivers/CMSIS/Device/ST/STM32H7xx/Include -I../Drivers/CMSIS/Include -O0 -ffunction-sections -fdata-sections -Wall -fstack-usage -MMD -MP -MF"Core/Src/FX_LMS.d" -MT"Core/Src/FX_LMS.o" --specs=nano.specs -mfpu=fpv5-d16 -mfloat-abi=hard -mthumb -o "Core/Src/FX_LMS.o"

and here is the source:

Upvotes: 2

Views: 273

Answers (1)

KamilCuk
KamilCuk

Reputation: 141145

You compiled the file for ARM architecture.

nm is for your local architecture. So most probably x86-64-pc-linux-gnu-nm or something like that.

arm-none-eabi-nm is for ARM architecture.

The endianess or some other quirks in the exact specification of ELF file may differ between architectures, which is most probably why you are seeing such artifacts.

Upvotes: 2

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