CMake: Catch troublesome build combinations for -DEXPAT_CHAR_TYPE=wchar_t

diff --git a/expat/CMakeLists.txt b/expat/CMakeLists.txt
index 72c3212cc83cff7d6b433514b94dd995e6280ca4..6a2d291da559617c664ff7bf7120a938cb5428f0 100644 (file)
--- a/expat/CMakeLists.txt
+++ b/expat/CMakeLists.txt
@@ -123,6 +123,15 @@ elseif(EXPAT_CHAR_TYPE STREQUAL "ushort")
 elseif(EXPAT_CHAR_TYPE STREQUAL "wchar_t")
     set(_EXPAT_UNICODE ON)
     set(_EXPAT_UNICODE_WCHAR_T ON)
+    if(NOT WIN32)
+        string(FIND "${CMAKE_C_FLAGS}" "-fshort-wchar" _expat_short_wchar_found)
+        if(${_expat_short_wchar_found} EQUAL "-1")
+            message(SEND_ERROR "Configuration -DEXPAT_CHAR_TYPE=wchar_t requires -DCMAKE_{C,CXX}_FLAGS=-fshort-wchar (which was not found) and libc compiled with -fshort-wchar, too.")
+        endif()
+        if (EXPAT_BUILD_TOOLS)
+            message(SEND_ERROR "The xmlwf tool can not be built with option -DEXPAT_CHAR_TYPE=wchar_t outside of Windows. Please pass -DEXPAT_CHAR_TYPE=char or -DEXPAT_BUILD_TOOLS=OFF.")
+        endif()
+    endif()
 else()
     message(SEND_ERROR "Option -DEXPAT_CHAR_TYPE=(char|ushort|wchar_t) cannot be \"${EXPAT_CHAR_TYPE}\".")
 endif()