Build broken

[Chris Sherlock]

I folks, after the upgrade of icu, it appears that the build is breaking:

/usr/bin/make -j 1 -rs -f /home/chris/repos/LibreOffice/core/Makefile.gbuild
[build MOD] accessibility
[build MOD] animations
[build MOD] avmedia
[build LNK] Executable/transex3
/home/chris/repos/LibreOffice/core/solver/unxlngi6.pro/lib/libtransex.a(po.o):
In function `(anonymous namespace)::lcl_EscapeTags(rtl::OString
const&)':
po.cxx:(.text+0x2697): undefined reference to
`icu_49::UnicodeString::UnicodeString(unsigned short const*, int)'
po.cxx:(.text+0x26b6): undefined reference to
`icu_49::UnicodeString::~UnicodeString()'
po.cxx:(.text+0x26d8): undefined reference to
`icu_49::UnicodeString::UnicodeString(unsigned short const*, int)'
po.cxx:(.text+0x26f7): undefined reference to
`icu_49::RegexMatcher::RegexMatcher(icu_49::UnicodeString const&,
unsigned int, UErrorCode&)'
po.cxx:(.text+0x270c): undefined reference to
`icu_49::RegexMatcher::reset(icu_49::UnicodeString const&)'
po.cxx:(.text+0x2827): undefined reference to
`icu_49::RegexMatcher::start(UErrorCode&) const'
po.cxx:(.text+0x283d): undefined reference to
`icu_49::UnicodeString::~UnicodeString()'
po.cxx:(.text+0x2855): undefined reference to
`icu_49::RegexMatcher::find(long long, UErrorCode&)'
po.cxx:(.text+0x28fe): undefined reference to
`icu_49::UnicodeString::~UnicodeString()'
po.cxx:(.text+0x2914): undefined reference to
`icu_49::RegexMatcher::~RegexMatcher()'
po.cxx:(.text+0x292a): undefined reference to
`icu_49::UnicodeString::~UnicodeString()'
po.cxx:(.text+0x2bf4): undefined reference to
`icu_49::RegexMatcher::group(UErrorCode&) const'
po.cxx:(.text+0x2c1c): undefined reference to
`icu_49::RegexMatcher::~RegexMatcher()'
po.cxx:(.text+0x2c2a): undefined reference to
`icu_49::UnicodeString::~UnicodeString()'
collect2: error: ld returned 1 exit status
make[1]: *** [/home/chris/repos/LibreOffice/core/workdir/unxlngi6.pro/LinkTarget/Executable/transex3]
Error 1
make: *** [build] Error 2

Regards,
Chris Sherlock