Bug#1143853: libcgns: FTBFS: dpkg-gensymbols: error: some symbols or patterns disappeared in the symbols file: see diff output below

Package: src:libcgns
Version: 4.5.0-1
Severity: serious
Tags: ftbfs forky sid

Dear maintainer:

During a rebuild of all packages in unstable, this package failed to build.

Below you will find the last part of the build log (probably the most
relevant part, but not necessarily). If required, the full build log
is available here:

https://people.debian.org/~sanvila/build-logs/202608/

About the archive rebuild: The build was made on virtual machines from AWS,
using sbuild and a reduced chroot with only build-essential packages.

If you cannot reproduce the bug please contact me privately, as I
am willing to provide ssh access to a virtual machine where the bug is
fully reproducible.

If this is really a bug in one of the build-depends, please use
reassign and add an affects on src:libcgns, so that this is still
visible in the BTS web page for this package.

Thanks.

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[...]
dpkg-gensymbols: error: some symbols or patterns disappeared in the symbols file: see diff output below
dpkg-gensymbols: warning: debian/libcgns4.5/DEBIAN/symbols does not match completely debian/libcgns4.5.symbols
--- debian/libcgns4.5.symbols (libcgns4.5_4.5.0-1_amd64)
+++ dpkg-gensymbolsvnDZ48       2026-08-07 09:57:14.063808532 +0000
@@ -203,7 +203,7 @@
  ZoneTypeName@Base 4.5.0
  __cgns_MOD___copy___iso_c_binding_C_ptr@Base 4.5.0
  __cgns_MOD___def_init___iso_c_binding_C_ptr@Base 4.5.0
- __cgns_MOD___vtab___iso_c_binding_C_ptr@Base 4.5.0
+#MISSING: 4.5.0-1# __cgns_MOD___vtab___iso_c_binding_C_ptr@Base 4.5.0
  __cgns_MOD_angleunitsname@Base 4.5.0
  __cgns_MOD_arbitrarygridmotiontypename@Base 4.5.0
  __cgns_MOD_areatypename@Base 4.5.0
dh_makeshlibs: error: failing due to earlier errors
make: *** [debian/rules:25: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess failed with exit status 2