diff -urp libreplaygain_r475.orig/src/CMakeLists.txt libreplaygain_r475/src/CMakeLists.txt
--- libreplaygain_r475.orig/src/CMakeLists.txt	2009-07-31 07:03:57.000000000 -0500
+++ libreplaygain_r475/src/CMakeLists.txt	2019-06-21 14:38:53.507794158 -0500
@@ -5,5 +5,6 @@ set_target_properties(replaygain-static
 
 add_library(replaygain-shared SHARED gain_analysis)
 set_target_properties(replaygain-shared PROPERTIES OUTPUT_NAME replaygain CLEAN_DIRECT_OUTPUT 1 VERSION 1.0.0 SOVERSION 1)
+target_link_libraries(replaygain-shared -lm)
 
 install(TARGETS replaygain-static replaygain-shared LIBRARY DESTINATION "lib${LIB_SUFFIX}" ARCHIVE DESTINATION "lib${LIB_SUFFIX}")