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Date: Tue, 24 May 2022 07:54:43 +0200
From: Kuba Kazimierczak <>
Subject: Linking musl with -shared -static - is this supported?

Hi, I'm on Alpine Linux, musl version 1.2.2. I'm attempting to create a 
statically-linked shared object using "-shared -static" and use it in a 
driver program as follows:

/tmp # cat lib.c
#include <stdlib.h>

unsigned int add(unsigned int a, unsigned int b)
     return (a+b);
/tmp # cat main.c
#include <stdio.h>

extern unsigned int add(unsigned int a, unsigned int b);

int main(void)
     printf("%d\n", add(1,2));
     return 0;
/tmp # clang-14 -g -c -fPIC lib.c
/tmp # clang-14 -shared -static -o lib.o
/tmp # clang-14 -g -L. main.c -o main -llib
/tmp # LD_LIBRARY_PATH=$PWD ./main
Segmentation fault

The segfault happens in musl's malloc implementation internals:

#0  0x00007f9c882adc7a in get_random_secret () at 
#1  __malloc_alloc_meta () at src/malloc/mallocng/malloc.c:50
#2  0x00007f9c882ae11b in alloc_group (req=1, sc=0) at 
#3  alloc_slot (sc=sc@...ry=0, req=req@...ry=1) at 
#4  0x00007f9c882ae646 in __libc_malloc_impl (n=1) at 
#5  0x00007f9c882ad208 in add (a=1, b=2) at lib.c:5
#6  0x000055909082f22e in main () at main.c:7

I see get_random_secret is trying to use struct __libc.argv, which is 
probably not initialized in this case.

Is this use case supported at all?

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