How to prevent strip from removing ar archive's index?

Question

I wrote a library that contains a.c and b.c, and another program c.c that uses this library. I have archived the library using ar to distribute it. Here are the commands I use:

gcc -g -c -o a.o a.c    # Compile a.c
gcc -g -c -o b.o b.c    # Compile b.c
ar r ab.a a.o b.o       # Generate library ab.a

gcc -o c c.c ab.a       # Compile c.c

Everything works fine until now. But I want to strip some sections in ab.a (e.g. debug info, internal functions), so I run strip --keep-symbol=... ab.a on the library. Now I cannot compile c.c any more. The error I get is:

+ gcc -o c c.c ab.a
/usr/bin/ld: ab.a: error adding symbols: archive has no index; run ranlib to add one
collect2: error: ld returned 1 exit status

If I run ranlib ab.a after strip, everything works fine. My question is: is it possible to change the arguments in the strip command, so that I do not need to run ranlib ab.a?

---

Complete example

a.c:

int a1()
{
    return 1;
}

int a2()
{
    return 2;
}

b.c:

int b1()
{
    return 3;
}

int b2()
{
    return 4;
}

c.c:

#include <stdio.h>

int a1();
int a2();
int b1();
int b2();

int main()
{
    printf("%d ", a1());
    printf("%d ", a2());
    printf("%d ", b1());
    printf("%d\n", b2());
}

Bash script to the "archive has no index" error:

gcc -g -c -o a.o a.c
gcc -g -c -o b.o b.c
ar r ab.a a.o b.o
strip --keep-symbol={a1,a2,b1,b2} ab.a
# ranlib ab.a
gcc -o c c.c ab.a
./c

Run the bash script

• Run the bash script directly -> see the error
• Comment the strip line -> success (symbols not stripped)
• Uncomment the ranlib line -> success

Software versions I am using:

• gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9)
• GNU ar version 2.35-18.fc33
• GNU strip version 2.35-18.fc33
• GNU ranlib version 2.35-18.fc33