fix linking exe against matlab libs on ubuntu (once again the compile…

…r here was overly sensitive about the order of the arguments)

cmake/mex.cmake

@@ -87,9 +87,10 @@ function(mex_setup)
 endfunction()
 
 function(add_mex)
-  # useage:  add_mex(target source1 source2 [OBJECT]) 
-  # if OBJECT is passed in, then it doesn't expect a mexFunction symbol to be defined, and compiles it to e.g., libtarget.so, for eventual linking against another mex file
+  # useage:  add_mex(target source1 source2 [SHARED,EXECUTABLE]) 
   # note: builds the mex file inplace (not into some build directory)
+  # if SHARED is passed in, then it doesn't expect a mexFunction symbol to be defined, and compiles it to e.g., libtarget.so, for eventual linking against another mex file
+  # if EXECUTABLE is passed in, then it adds an executable target, which is linked against the appropriate matlab libraries.
 
   list(GET ARGV 0 target)
   list(REMOVE_AT ARGV 0)
@@ -145,7 +146,22 @@ function(add_mex)
     COMPILE_FLAGS "-DMATLAB_MEX_FILE" 
     )
 
-  if (isshared EQUAL -1 AND isexe EQUAL -1)
+  if (isexe GREATER -1)
+    # see note below
+    if (NOT TARGET last) 
+      set(dummy_c_file ${CMAKE_CURRENT_BINARY_DIR}/dummy.c)
+      add_custom_command(COMMAND ${CMAKE_COMMAND} -E touch ${dummy_c_file}
+                         OUTPUT ${dummy_c_file})
+      add_library(last STATIC ${dummy_c_file})
+      target_link_libraries(last ${MEX_CLIBS})
+    endif()
+
+    target_link_libraries(${target} last)
+  elseif (isshared GREATER -1)
+    set_target_properties(${target} PROPERTIES
+      LINK_FLAGS "${MEX_CLIBS}"
+      )
+  else()
     # note: on ubuntu, gcc did not like the MEX_CLIBS coming along with LINK_FLAGS (it only works if they appear after the input files).  this is a nasty trick that I found online
     if (NOT TARGET last) 
       set(dummy_c_file ${CMAKE_CURRENT_BINARY_DIR}/dummy.c)
@@ -165,10 +181,6 @@ function(add_mex)
       LIBRARY_OUTPUT_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"   
       )
     target_link_libraries(${target} last)
-  else()
-    set_target_properties(${target} PROPERTIES
-      LINK_FLAGS "${MEX_CLIBS}"
-      )
   endif()
 
   # todo: add CLIBS or CXXLIBS to LINK_FLAGS selectively based in if it's a c or cxx target (always added CXX above)