Hi,
I reproduced this on current libgdiplus 6.1+dfsg-1.2 and prepared a tested
fix in debian/rules. Attached is the scoped debian/rules fix I prepared
against libgdiplus 6.1+dfsg-1.2.
For this bug specifically, the fix enables verbose build output through
DH_VERBOSE=1, passes --disable-silent-rules at configure time and uses
dh_auto_build with V=1. With that change, the build logs include the full
compiler and linker command lines instead of only short automake status lines.
Validation on the patched tree: dpkg-buildpackage -b succeeds;
dpkg-buildpackage -S succeeds afterwards on the same tree; a clean
unstable-amd64-sbuild succeeds; piuparts passes when run for amd64.
The separate vendored Googletest compatibility failure is tracked in #1135544
and is not part of this patch.
Since libgdiplus is currently orphaned (#1079870), I am sending this as an
adoption/QA-style handoff rather than assuming an active maintainer workflow.
Regards,
James