diff --git a/configure b/configure
index 9d0d940e56..75b39aa55c 100755
--- a/configure
+++ b/configure
@@ -40373,10 +40373,14 @@ case "${host}" in
         ;;
 esac
 
-WX_CPPFLAGS=$CPPFLAGS
-WX_CFLAGS=$CFLAGS
-WX_CXXFLAGS=$CXXFLAGS
-WX_LDFLAGS=$LDFLAGS
+dedup_flags () { printf %s "$@" | awk -v RS=' +' -v ORS=' ' '!seen[$0]++'; }
+
+WX_CPPFLAGS=`dedup_flags "$CPPFLAGS"`
+WX_CFLAGS=`dedup_flags "$CFLAGS"`
+WX_CXXFLAGS=`dedup_flags "$CXXFLAGS"`
+
+LDFLAGS=`printf %s "$LDFLAGS" | sed 's/-framework  */-framework_/g'`
+WX_LDFLAGS=`dedup_flags "$LDFLAGS" | sed 's/-framework_/-framework /g'`
 
 CPPFLAGS=$USER_CPPFLAGS
 CFLAGS=$USER_CFLAGS
diff --git a/configure.in b/configure.in
index b1648b6d70..ccf8691dd8 100644
--- a/configure.in
+++ b/configure.in
@@ -8269,10 +8269,19 @@ esac
 
 dnl Set the flags to be used for the library build itself using the flag names
 dnl used everywhere above.
-WX_CPPFLAGS=$CPPFLAGS
-WX_CFLAGS=$CFLAGS
-WX_CXXFLAGS=$CXXFLAGS
-WX_LDFLAGS=$LDFLAGS
+dnl
+dnl Also get rid of duplicates in the flags, which results in dramatically
+dnl shorter build logs and so is well worth it.
+dedup_flags () { printf %s "$@" | awk -v RS=' +' -v ORS=' ' '!seen[[$0]]++'; }
+
+WX_CPPFLAGS=`dedup_flags "$CPPFLAGS"`
+WX_CFLAGS=`dedup_flags "$CFLAGS"`
+WX_CXXFLAGS=`dedup_flags "$CXXFLAGS"`
+
+dnl For link flags we can use "-framework" multiple times and all of their
+dnl occurrences need to be preserved, so add extra pre/post-processing.
+LDFLAGS=`printf %s "$LDFLAGS" | sed 's/-framework  */-framework_/g'`
+WX_LDFLAGS=`dedup_flags "$LDFLAGS" | sed 's/-framework_/-framework /g'`
 
 dnl Restore the original user-specified flags values, we won't run any tests
 dnl using them any more.