Building a pure C program produces a binary with unneded dependencies

[alxrmorozov]

a.c:

int main() { return 0; }

jamroot.jam:

exe a : a.c ;

Build:

$ b2 toolset=gcc -d+2
common.mkdir bin

        mkdir -p "bin"

common.mkdir bin/gcc-8

        mkdir -p "bin/gcc-8"

common.mkdir bin/gcc-8/debug

        mkdir -p "bin/gcc-8/debug"

gcc.compile.c bin/gcc-8/debug/a.o

    "g++" -x c -fPIC -O0 -fno-inline -Wall -g     -c -o "bin/gcc-8/debug/a.o" "a.c"

gcc.link bin/gcc-8/debug/a

    "g++"    -o "bin/gcc-8/debug/a" -Wl,--start-group "bin/gcc-8/debug/a.o"  -Wl,-Bstatic  -Wl,-Bdynamic  -Wl,--end-group -fPIC -g

Resulting binary dependencies:

$ ldd bin/gcc-8/debug/a
        linux-vdso.so.1 (0x00007ffd25cf3000)
        libstdc++.so.6 => /lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f7373bab000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f7373a28000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f7373a0e000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f737384d000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f7373d5e000)

If I build with gcc I get much less dependencies:

$ gcc a.c -o a
$ ldd ./a
        linux-vdso.so.1 (0x00007ffce34e5000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f1774547000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f1774737000)

$ b2 --version
B2 4.2-git

$ g++ --version
g++ (Debian 8.3.0-6) 8.3.0
Copyright (C) 2018 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ cat /etc/debian_version
10.7
$ arch
x86_64

[stale]

Thank you for your contributions. Main development of B2 has moved to https://github.com/bfgroup/b2
This issue has been automatically marked as "transition" to indicate the potential for needing transition to the new B2 development project.