memset initialization of struct freeze

Question

Some library I use in an embedded (STM32F103) project initializes it's structs with memset() which for some reason causes the program to stop responding/hang.

To test this I used:

typedef struct
{
    uint8_t b;
    uint8_t c;
} testStruct;

testStruct d = { .b = 0, .c = 0 };

memset(&d, 0, sizeof(d));

And sure enough this causes the same behavior. Using memset() on an array appears to work fine.

I have run out of ideas as to what the problem could be and even thought maybe its a memory alignment issue and tried using __attribute__((aligned(4),packed)) on the struct but this also did not help.

I am using GCC for ARM to compile the code:

arm-none-eabi-gcc -std=c11 --specs=nosys.specs -fno-exceptions -Wall -O0 -nostartfiles -mcpu=cortex-m0 -mthumb -mcpu=cortex-m3 -march=armv7-m -I %IncludeDir% -o %WorkingDir%bin\main.elf -T %WorkingDir%stm32f103c8t6.ld %WorkingDir%systick.c %WorkingDir%can.c %WorkingDir%uart.c %WorkingDir%fifo.c %WorkingDir%main.c %WorkingDir%libcanard\canard.c %LibDir%libopencm3_stm32f1.a

Any ideas as to what I am missing here?

EDIT:

Below is the full test code. My test is simple, I am blinking a LED. When memset() is present the code never reaches the main loop to start blinking the LED. When I comment memset() then the LED blinks.

#define STM32F1
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/usart.h>
#include <string.h>
#include "systick.h"

void loopToggleLED(uint32_t tnow)
{
    static uint32_t tPrevToggleLoop;
    static bool LEDisOn;

    if ((tnow - tPrevToggleLoop) < 1000000)
        return;

    tPrevToggleLoop = tnow;

    if (!LEDisOn)
    {
        gpio_clear(GPIOC,GPIO13);       // LED on
        LEDisOn = true;
    }
    else
    {
        gpio_set(GPIOC,GPIO13);         // LED off
        LEDisOn = false;
    }   
}

int main()
{
    rcc_clock_setup_in_hse_8mhz_out_72mhz();
    // Enable GPIOC clock. 
    rcc_periph_clock_enable(RCC_GPIOC);

    // Set GPIO8 (in GPIO port C) to 'output push-pull'.
    gpio_set_mode(GPIOC,GPIO_MODE_OUTPUT_2_MHZ,
              GPIO_CNF_OUTPUT_PUSHPULL,GPIO13);

    systick_Init();

    typedef struct
    {
        uint8_t b;
        uint8_t c;
    } testStruct;

    testStruct d = { .b = 0, .c = 0 };

    // Commenting memset() below allows the code to enter the loop below and blink the LEDs
    memset(&d, 0, sizeof(d));

    uint32_t tnow;
    for (;;) 
    {
        tnow = systick_Micros();    
        loopToggleLED(tnow);            
    }

    return 0;
}

Answer 1

Solved! As KamilCuk pointed out, I mistakenly used mcpu flags for both cortex-m0 and cortex-m3. After removing -mcpu=cortex-m0 memset works again as expected! Thanks for pointing it out and helping to solve this!