Strange circular dependency on Linux Mint 19.2

[Gmail <76nemo76%gmx.ch@localhost>]

Hi All,
        When trying to compile "libtool" on Linux Mint 19.2
(the last version), I get a strange problem of circular dependency.
The last stable version of PKGSRC is used.

This is a big problem since without libtool almost no
package can be compiled.

The proble arise when compiling "nbpatch". The dependency seems
to be about "gcc3" (why a such old version of gcc?).

Do you have an idea?

Here is the resulting log:

=> Bootstrap dependency digest>=20010302: found digest-20190127
===> Skipping vulnerability checks.
WARNING: No /opt/pkg/pkgdb/pkg-vulnerabilities file found.
WARNING: To fix run: `/opt/pkg/sbin/pkg_admin -K /opt/pkg/pkgdb fetch-pkg-vulnerabilities'.
===> Installing dependencies for libtool-2.4.6
=> Tool dependency nbpatch-[0-9]*: NOT found
=> Verifying package-install for ../../devel/nbpatch
===> Skipping vulnerability checks.
WARNING: No /opt/pkg/pkgdb/pkg-vulnerabilities file found.
WARNING: To fix run: `/opt/pkg/sbin/pkg_admin -K /opt/pkg/pkgdb fetch-pkg-vulnerabilities'.
===> Installing dependencies for nbpatch-20151107
=> Build dependency gcc3-c>=3.3.5nb1: NOT found
=> Verifying package-install for ../../lang/gcc3-c
=> Bootstrap dependency digest>=20010302: found digest-20190127
===> Skipping vulnerability checks.
WARNING: No /opt/pkg/pkgdb/pkg-vulnerabilities file found.
WARNING: To fix run: `/opt/pkg/sbin/pkg_admin -K /opt/pkg/pkgdb fetch-pkg-vulnerabilities'.
=> Checksum SHA1 OK for gcc-3.3.6.tar.bz2
=> Checksum RMD160 OK for gcc-3.3.6.tar.bz2
=> Checksum SHA512 OK for gcc-3.3.6.tar.bz2
===> Installing dependencies for gcc3-c-3.3.6nb1
=> Tool dependency nbpatch-[0-9]*: NOT found
=> Verifying package-install for ../../devel/nbpatch
ERROR: This package has set PKG_FAIL_REASON:
ERROR: Circular dependency detected
*** Error code 1

Stop.
bmake[3]: stopped in /opt/pkgsrc/devel/nbpatch
*** Error code 1

Stop.
bmake[2]: stopped in /opt/pkgsrc/lang/gcc3-c
*** Error code 1

Stop.
bmake[1]: stopped in /opt/pkgsrc/devel/nbpatch
*** Error code 1

Stop.
bmake: stopped in /opt/pkgsrc/devel/libtool