Bison bug here
https://lists.gnu.org/archive/html/bug-bison/2023-12/msg00001.html

Building source-highlight 3.1.9 fails with the following error:


```
/bin/sh ../../libtool  --tag=CXX   --mode=link x86_64-pc-linux-gnu-g++  -march=native -fstack-protector-all -O2 -pipe -fdiagnostics-color=always -frecord-gcc-switches -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 -fstack-clash-protection -Wformat -Werror=format-security -flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing -std=c++14 -L/usr/lib64 -version-info 4:1:0 -Wl,-O1 -Wl,--as-needed -Wl,--defsym=__gentoo_check_ldflags__=0 -o libsource-highlight.la -rpath /usr/lib64 fileutil.lo substfun.lo stopwatch.lo utils.lo ioexception.lo settings.lo versions.lo verbosity.lo sourcehighlight.lo styleparser.lo stylescanner.lo outlangdefparser.lo stylecssparser.lo stylecssscanner.lo outlangdefscanner.lo debuglistener.lo langmap.lo stylefileparser.lo langelem.lo statelangelem.lo langelems.lo statestartlangelem.lo stringlistlangelem.lo delimitedlangelem.lo langelemsprinter.lo namedsubexpslangelem.lo stringdef.lo highlightrule.lo highlighttoken.lo highlightstate.lo highlightrulefactory.lo highlightstateprinter.lo sourcehighlighter.lo sourcefilehighlighter.lo linenumgenerator.lo lineranges.lo regexranges.lo formatter.lo formattermanager.lo textstyle.lo textstyleformatter.lo bufferedoutput.lo preformatter.lo wordtokenizer.lo ctagscollector.lo readtags.lo ctagsformatter.lo srcuntabifier.lo textstyleformatterfactory.lo docgenerator.lo doctemplate.lo chartranslator.lo textstylebuilder.lo fileinfo.lo ctagsmanager.lo regexhighlightrule.lo regexrulefactory.lo regexpreprocessor.lo highlightstatebuilder.lo highlightbuilderexception.lo langdefmanager.lo langdefparser.lo langdefscanner.lo languageinfer.lo parserexception.lo stringtable.lo vardefinitions.lo sourcehighlightutils.lo instances.lo ../../gl/libgnu.la yywrap.lo -lboost_regex
libtool: link: x86_64-pc-linux-gnu-g++  -fPIC -DPIC -shared -nostdlib /usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../lib64/crti.o /usr/lib/gcc/x86_64-pc-linux-gnu/13/crtbeginS.o  .libs/fileutil.o .libs/substfun.o .libs/stopwatch.o .libs/utils.o .libs/ioexception.o .libs/settings.o .libs/versions.o .libs/verbosity.o .libs/sourcehighlight.o .libs/styleparser.o .libs/stylescanner.o .libs/outlangdefparser.o .libs/stylecssparser.o .libs/stylecssscanner.o .libs/outlangdefscanner.o .libs/debuglistener.o .libs/langmap.o .libs/stylefileparser.o .libs/langelem.o .libs/statelangelem.o .libs/langelems.o .libs/statestartlangelem.o .libs/stringlistlangelem.o .libs/delimitedlangelem.o .libs/langelemsprinter.o .libs/namedsubexpslangelem.o .libs/stringdef.o .libs/highlightrule.o .libs/highlighttoken.o .libs/highlightstate.o .libs/highlightrulefactory.o .libs/highlightstateprinter.o .libs/sourcehighlighter.o .libs/sourcefilehighlighter.o .libs/linenumgenerator.o .libs/lineranges.o .libs/regexranges.o .libs/formatter.o .libs/formattermanager.o .libs/textstyle.o .libs/textstyleformatter.o .libs/bufferedoutput.o .libs/preformatter.o .libs/wordtokenizer.o .libs/ctagscollector.o .libs/readtags.o .libs/ctagsformatter.o .libs/srcuntabifier.o .libs/textstyleformatterfactory.o .libs/docgenerator.o .libs/doctemplate.o .libs/chartranslator.o .libs/textstylebuilder.o .libs/fileinfo.o .libs/ctagsmanager.o .libs/regexhighlightrule.o .libs/regexrulefactory.o .libs/regexpreprocessor.o .libs/highlightstatebuilder.o .libs/highlightbuilderexception.o .libs/langdefmanager.o .libs/langdefparser.o .libs/langdefscanner.o .libs/languageinfer.o .libs/parserexception.o .libs/stringtable.o .libs/vardefinitions.o .libs/sourcehighlightutils.o .libs/instances.o .libs/yywrap.o  -Wl,--whole-archive ../../gl/.libs/libgnu.a -Wl,--no-whole-archive  -L/usr/lib64 -Wl,--as-needed -lboost_regex -L/usr/lib/gcc/x86_64-pc-linux-gnu/13 -L/usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L/usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../x86_64-pc-linux-gnu/lib -L/usr/lib/gcc/x86_64-pc-linux-gnu/13/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/x86_64-pc-linux-gnu/13/crtendS.o /usr/lib/gcc/x86_64-pc-linux-gnu/13/../../../../lib64/crtn.o  -march=native -fstack-protector-all -O2 -Werror=format-security -flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing -Wl,-O1 -Wl,--defsym=__gentoo_check_ldflags__=0   -Wl,-soname -Wl,libsource-highlight.so.4 -o .libs/libsource-highlight.so.4.0.1
../../../lib/srchilite/styleparser.cc:203:15: error: type 'union YYSTYPE' violates the C++ One Definition Rule [-Werror=odr]
../../../lib/srchilite/outlangdefparser.cc:233:15: note: a different type is defined in another translation unit
../../../lib/srchilite/styleparser.yy:68:23: note: the first difference of corresponding definitions is field 'string'
../../../lib/srchilite/outlangdefparser.yy:64:8: note: a field with different name is defined in another translation unit
../../../lib/srchilite/styleparser.cc:391:7: error: type 'union yyalloc' violates the C++ One Definition Rule [-Werror=odr]
../../../lib/srchilite/outlangdefparser.cc:420:7: note: a different type is defined in another translation unit
../../../lib/srchilite/styleparser.cc:394:11: note: the first difference of corresponding definitions is field 'yyvs_alloc'
../../../lib/srchilite/outlangdefparser.cc:423:11: note: a field of same name but different type is defined in another translation unit
../../../lib/srchilite/styleparser.cc:391:7: note: type 'union YYSTYPE' itself violates the C++ One Definition Rule
../../../lib/srchilite/langdefparser.h:127:16: error: 'langdef_lval' violates the C++ One Definition Rule [-Werror=odr]
../../../lib/srchilite/langdefparser.cc:1411:9: note: type 'union YYSTYPE' itself violates the C++ One Definition Rule
../../../lib/srchilite/langdefparser.cc:1411:9: note: 'langdef_lval' was previously declared here
lto1: some warnings being treated as errors
lto-wrapper: fatal error: x86_64-pc-linux-gnu-g++ returned 1 exit status
compilation terminated.
/usr/libexec/gcc/x86_64-pc-linux-gnu/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[4]: * [Makefile:996: libsource-highlight.la] Error 1
```