Prior to commit 1d709ea2f5 (cmGeneratorTarget: Propagate backtraces from
INTERFACE_LINK_LIBRARIES, 2021-12-15, v3.23.0-rc1~228^2), the value of
`INTERFACE_LINK_LIBRARIES` was a single string. If an unquoted
generator expression passed to `target_link_libraries` contained `;` and
became multiple arguments, they would all accumulate as a single
`;`-separated list in the value of `INTERFACE_LINK_LIBRARIES`. Since
that commit, each argument to `target_link_libraries` is placed in
`INTERFACE_LINK_LIBRARIES` as a separate entry, as has long been the
case for `LINK_LIBRARIES`. That behavior change broke projects that were
accidentally relying on accumulation in `INTERFACE_LINK_LIBRARIES` to
produce complete generator expressions containing `;`.
Teach `target_link_libraries` to accumulate consecutive non-keyword
arguments into a single entry before placing them in `LINK_LIBRARIES` or
`INTERFACE_LINK_LIBRARIES`. For example, treat `a b c` as if they were
written as `"a;b;c"`. This restores the previously accidental support
for unquoted generator expressions in `INTERFACE_LINK_LIBRARIES`, and
also enables it for `LINK_LIBRARIES`.
For now, do not drop the `target_link_libraries` documentation that
recommends quoting generator expressions. Quoting is still important to
populate `LINK_LIBRARIES` in CMake 3.22 and below, and is also good
practice to keep generator expressions whole.
Fixes: #23203
c1e812ad4f