LWIP_RAND uses newlib rand() and fails

[Gustavo_AR]

CubeMX generated project defines

#define LWIP_RAND() ((u32_t)rand())

which fails with the following call stack...

and the following assert text

assertion "REENT malloc succeeded" failed: file "/build/gnu-tools-for-stm32_12.3.rel1.20240612-1315/src/newlib/newlib/libc/stdlib/rand.c", line 82

Line 82 of rand.c is:

_REENT_CHECK_RAND48(reent);

which in turn ends up calling a malloc... 

I've read that reentrancy in newlib could cause problems, but I thought it would be memory corruption.

Is there a solution for this?

Thanks in advance!

[Imen.D · Accepted solution]

Hello @Gustavo_AR ,

Seems you have the same issue reported in these posts:

• STM32H735G-DK projects and APPLICATIONS ERRORS STM... - STMicroelectronics Community
• assertion "REENT malloc succeeded" failed - STMicroelectronics Community

Hope the shared posts will help you, otherwise please share more details about the device, the tools version used and how to reproduce the issue.

[Gustavo_AR]

Thanks @Imen.D I've fixed it by 

/* Defining malloc/free should overwrite the standard versions provided by the compiler. */

void *malloc(size_t size) {
    /* Call the FreeRTOS version of malloc. */
    return pvPortMalloc(size);
}

void free(void *ptr) {
    /* Call the FreeRTOS version of free. */
    vPortFree(ptr);
}