Handle/allow arbitrary linker arguments (TriBITSPub#299, TriBITSPub#433)

Turns out some Trilinos configure scripts (including some of the ATDM Trilinos
configure scripts) use arbitary linker arguments like '-mkl' that are not -L
or -l.  These arguments need to be moved forward on the link link in the
'all_libs' target.  Since this is not very general, I added a 'NOTE' printed
to STDOUT in order to warn about this.

NOTE: This now allows an agument like: '-o some-name' and it will move '-o'
forward and in the next commit the bare 'some-name' arg will be interepreted
as a library name and be handled the same as '-l<libname>'.  But obviously
splitting up the arguments `-o some-name` by moving '-o' forward by itself and
treating `some-name` as a link library is just wrong but I don't see how we
can avoid that.

test/core/CMakeLists.txt

@@ -145,7 +145,7 @@ tribits_add_advanced_test( TribitsExternalPackageWriteConfigFile_UnitTests
       -DCURRENT_TEST_DIRECTORY=${CMAKE_CURRENT_BINARY_DIR}
       -P "${CMAKE_CURRENT_SOURCE_DIR}/TribitsExternalPackageWriteConfigFile_UnitTests.cmake"
     PASS_REGULAR_EXPRESSION_ALL
-      "Final UnitTests Result: num_run = 31"
+      "Final UnitTests Result: num_run = 35"
       "Final UnitTests Result: PASSED"
   )
 

test/core/TribitsExternalPackageWriteConfigFile_UnitTests.cmake

@@ -348,6 +348,48 @@ target_link_libraries(SomeTpl::lib3
 endfunction()
 
 
+function(unittest_tribits_external_package_process_libraries_list_incl_dirs_0_link_opt_1)
+
+  message("\n***")
+  message("*** Testing tribits_external_package_process_libraries_list(): incl dirs 0, link opt 1")
+  message("***\n")
+
+  set(tplName SomeTpl)
+  set(TPL_${tplName}_LIBRARIES "-mkl")
+
+  set(configFileFragStr "#beginning\n\n")
+
+  set(MESSAGE_WRAPPER_UNIT_TEST_MODE ON)
+  global_null_set(MESSAGE_WRAPPER_INPUT)
+
+  tribits_external_package_process_libraries_list( ${tplName}
+    LIB_TARGETS_LIST_OUT libTargetsList
+    LIB_LINK_FLAGS_LIST_OUT libLinkFlagsList
+    CONFIG_FILE_STR_INOUT configFileFragStr
+    )
+
+  unittest_compare_const( MESSAGE_WRAPPER_INPUT
+    "NOTE: Moving the general link argument '-mkl' in TPL_${tplName}_LIBRARIES forward on the link line which may change the link and break the link!"
+    )
+
+  unittest_compare_const( libTargetsList
+    ""
+    )
+
+  unittest_compare_const( libLinkFlagsList
+    "-mkl"
+    )
+
+  unittest_string_block_compare( configFileFragStr
+[=[
+#beginning
+
+]=]
+    )
+
+endfunction()
+
+
 function(unittest_tribits_external_package_process_libraries_list_incl_dirs_0_lib_opts_2_2_lib_files_1)
 
   message("\n***")
@@ -692,7 +734,7 @@ function(unittest_tribits_external_package_write_config_file_str_incl_dirs_1_bad
     tplConfigFileStr )
 
   unittest_compare_const( MESSAGE_WRAPPER_INPUT
-    "SEND_ERROR;ERROR: Can't handle argument 'some-other-option' in list TPL_SomeTpl_LIBRARIES;SEND_ERROR;ERROR: Can't handle argument '-o' in list TPL_SomeTpl_LIBRARIES"
+    "SEND_ERROR;ERROR: Can't handle argument 'some-other-option' in list TPL_SomeTpl_LIBRARIES;NOTE: Moving the general link argument '-o' in TPL_SomeTpl_LIBRARIES forward on the link line which may change the link and break the link!"
     )
 
   unittest_string_block_compare( tplConfigFileStr
@@ -723,6 +765,7 @@ target_include_directories(SomeTpl::all_libs SYSTEM
   )
 target_link_options(SomeTpl::all_libs
   INTERFACE "-L/some/explicit/path2"
+  INTERFACE "-o"
   INTERFACE "-L/some/explicit/path1"
   )
 
@@ -751,6 +794,7 @@ unittest_tribits_external_package_process_libraries_list_incl_dirs_0_lib_opts_1_
 unittest_tribits_external_package_process_libraries_list_incl_dirs_0_lib_opts_2_2()
 unittest_tribits_external_package_process_libraries_list_incl_dirs_0_lib_opts_3_3()
 unittest_tribits_external_package_process_libraries_list_incl_dirs_0_lib_opts_2_2_lib_files_1()
+unittest_tribits_external_package_process_libraries_list_incl_dirs_0_link_opt_1()
 unittest_tribits_external_package_process_libraries_list_duplicate_libs()
 
 unittest_tribits_external_package_write_config_file_str_incl_dirs_0_lib_files_1()
@@ -761,4 +805,4 @@ unittest_tribits_external_package_write_config_file_str_incl_dirs_2_lib_opts_2_2
 unittest_tribits_external_package_write_config_file_str_incl_dirs_1_bad_lib_args()
 
 # Pass in the number of expected tests that must pass!
-unittest_final_result(31)
+unittest_final_result(35)

tribits/core/package_arch/TribitsExternalPackageWriteConfigFile.cmake

@@ -230,7 +230,7 @@ endfunction()
 #
 # Read the ``TPL_<tplName>_LIBRARIES` list variable and produce the string for
 # the IMPORTED targets commands and return list of targets and left over
-# linker flags..
+# linker flags.
 #
 # Usage::
 #
@@ -243,17 +243,17 @@ endfunction()
 #
 # The arguments are:
 #
-#   ``<tplName>``: Name of the external package/TPL
+#   ``<tplName>``: [In] Name of the external package/TPL
 #
-#   ``<libTargetsListOut>``: Name of list variable that will be set with the
-#   list of IMPORTED library targets generated from this list.
+#   ``<libTargetsListOut>``: [Out] Name of list variable that will be set with
+#   the list of IMPORTED library targets generated from this list.
 #
-#   ``<libLinkFlagsListOut>``: Name of list variable that will be set with the
-#   list of ``-L<dir>`` library directoy paths.
+#   ``<libLinkFlagsListOut>``: [Out] Name of list variable that will be set
+#   with the list of ``-L<dir>`` library directoy paths.
 #
-#   ``<configFileFragStrInOut>``: A string variable that will be appended with
-#   the IMPORTED library commands for the list of targts given in
-#   ``<libTargetsList>``.
+#   ``<configFileFragStrInOut>``: [Inout] A string variable that will be
+#   appended with the IMPORTED library commands for the list of targts given
+#   in ``<libTargetsList>``.
 #
 function(tribits_external_package_process_libraries_list  tplName)
 
@@ -294,6 +294,9 @@ function(tribits_external_package_process_libraries_list  tplName)
         "ERROR: Can't handle argument '${libentry}' in list TPL_${tplName}_LIBRARIES")
     elseif (libEntryType STREQUAL "LIB_DIR_LINK_OPTION")
       list(APPEND libLinkFlagsList "${libentry}")
+    elseif (libEntryType STREQUAL "GENERAL_LINK_OPTION")
+      message_wrapper("NOTE: Moving the general link argument '${libentry}' in TPL_${tplName}_LIBRARIES forward on the link line which may change the link and break the link!")
+      list(APPEND libLinkFlagsList "${libentry}")
     else()
       tribits_external_package_process_libraries_list_library_entry(
         ${tplName}  "${libentry}"  ${libEntryType}  libTargets  lastLib  configFileStr )
@@ -329,14 +332,20 @@ endfunction()
 #   ``LIB_DIR_LINK_OPTION``: A library directory search option of the form
 #   ``-L<dir>``
 #
+#   ``GENERAL_LINK_OPTION``: Some other general link option that starts with
+#   ``-`` but is not ``-l`` or ``-L``.
+#
 #   ``UNSUPPORTED_LIB_ENTRY``: An unsupported lib option
 #
 function(tribits_tpl_libraries_entry_type  libentry  libEntryTypeOut)
+  string(SUBSTRING "${libentry}" 0 1 firstCharLibEntry)
   string(SUBSTRING "${libentry}" 0 2 firstTwoCharsLibEntry)
   if (firstTwoCharsLibEntry STREQUAL "-l")
     set(libEntryType LIB_NAME_LINK_OPTION)
   elseif (firstTwoCharsLibEntry STREQUAL "-L")
     set(libEntryType LIB_DIR_LINK_OPTION)
+  elseif (firstCharLibEntry STREQUAL "-")
+    set(libEntryType GENERAL_LINK_OPTION)
   elseif (IS_ABSOLUTE "${libentry}")
     set(libEntryType FULL_LIB_PATH)
   else()