Bug#1009675: GCC toolchain is broken on Debian 11 aarch64 when creating shared libraries

[Sad Clouds <cryintothebluesky@gmail.com>]

Package: gcc
Version: 10.2.1


When I try to create shared libraries and link to them, I get
"undefined reference to" errors, where linker cannot find referenced
symbols in the shared library.

I tried the same program on Debian 10 x86_64 and it links correctly.

The issue can be reproduced with the following steps:

Create libtest.c:
cat > libtest.c << 'EOF'
#include <stdio.h>

void test(void)
{
        printf("This is a test\n");
}
EOF

Create main.c that uses symbols from libtest:
cat > main.c << 'EOF'
void test(void);
int main(void)
{
        test();
}
EOF

Create libtest.so shared library:
gcc -O2 -fPIC -DPIC -c libtest.c && \
gcc -O2 -fPIC -DPIC -shared -Wl,--default-symver -Wl,-soname,libtest.so.
1 -o libtest.so.1.0 libtest.o && \ ln -sf libtest.so.1.0 libtest.so

Create main executable, linking it with libtest.so:
gcc -O2 -c main.c && \
gcc -O2 -L./ -ltest -o main main.c

The above step fails with the following error:
/bin/ld: /tmp/ccZq9tP1.o: in function `main':
main.c:(.text.startup+0x8): undefined reference to `test'
collect2: error: ld returned 1 exit status


Below are the specifics of my dev environment:

$ uname -a
Linux rp4 5.10.0-13-arm64 #1 SMP Debian 5.10.106-1 (2022-03-17) aarch64
GNU/Linux

$ cat /etc/os-release 
PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/";
SUPPORT_URL="https://www.debian.org/support";
BUG_REPORT_URL="https://bugs.debian.org/";

$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/aarch64-linux-gnu/10/lto-wrapper
Target: aarch64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian
10.2.1-6' --with-bugurl=file:///usr/share/doc/gcc-10/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 --prefix=/usr
--with-gcc-major-version-only --program-suffix=-10
--program-prefix=aarch64-linux-gnu- --enable-shared
--enable-linker-build-id --libexecdir=/usr/lib
--without-included-gettext --enable-threads=posix --libdir=/usr/lib
--enable-nls --enable-bootstrap --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-libquadmath --disable-libquadmath-support --enable-plugin
--enable-default-pie --with-system-zlib
--enable-libphobos-checking=release --with-target-system-zlib=auto
--enable-objc-gc=auto --enable-multiarch --enable-fix-cortex-a53-843419
--disable-werror --enable-checking=release --build=aarch64-linux-gnu
--host=aarch64-linux-gnu --target=aarch64-linux-gnu
--with-build-config=bootstrap-lto-lean --enable-link-mutex Thread
model: posix Supported LTO compression algorithms: zlib zstd gcc
version 10.2.1 20210110 (Debian 10.2.1-6)