I wrote an extension in C++ that uses libtidy, and it runs perfectly under PHP when I compile PHP --with-tidy. However, it would be nice to have the extension run on a vanilla PHP. When I try to use the extension, I get something like: PHP Warning: PHP Startup: Unable to load dynamic library 'extension.so': undefined symbol: tidyCleanAndRepair in Unknown on line 0 and the extension is not loaded. Obviously, the official tidy extension works fine. I have the relevant libtidy development packages installed on the system, and it compiles+links without a problem. I have tried to look through the code for the tidy extension, but it is a huge mass of macros - copying pieces at random felt like cargo code. Besides linking to the library with PHP_ADD_LIBRARY_WITH_PATH(tidy, $TIDY_LIBDIR, TIDY_SHARED_LIBADD), Is there a PHP extension or C statement that fixes this error? Thanks in advance!!