BUG: fix setting of c flags

Modules/Platform/HP-UX.cmake

@@ -47,6 +47,8 @@ ELSE(CMAKE_COMPILER_IS_GNUCXX)
     SET (CMAKE_CXX_FLAGS_MINSIZEREL "-O3")
     SET (CMAKE_CXX_FLAGS_RELEASE "-O2")
     SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "-g")
-    SET (CMAKE_C_FLAGS "")
   ENDIF(NOT CMAKE_CXX_FLAGS)
+  IF(NOT CMAKE_C_FLAGS)
+    SET (CMAKE_C_FLAGS "")
+  ENDIF(NOT CMAKE_C_FLAGS)
 ENDIF(CMAKE_COMPILER_IS_GNUCXX)

Modules/Platform/IRIX.cmake

@@ -12,8 +12,10 @@ IF(NOT CMAKE_COMPILER_IS_GNUCXX)
     SET (CMAKE_CXX_FLAGS_MINSIZEREL "-O3")
     SET (CMAKE_CXX_FLAGS_RELEASE "-O2")
     SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2")
-    SET (CMAKE_C_FLAGS "")
   ENDIF(NOT CMAKE_CXX_FLAGS)
+  IF(NOT CMAKE_C_FLAGS)
+    SET (CMAKE_C_FLAGS "")
+  ENDIF(NOT CMAKE_C_FLAGS)
 ELSE(NOT CMAKE_COMPILER_IS_GNUCXX)
   INCLUDE(${CMAKE_ROOT}/Modules/Platform/gcc.cmake)
 ENDIF(NOT CMAKE_COMPILER_IS_GNUCXX)

Modules/Platform/IRIX64.cmake

@@ -13,8 +13,10 @@ IF(NOT CMAKE_COMPILER_IS_GNUCXX)
     SET (CMAKE_CXX_FLAGS_MINSIZEREL "-O3")
     SET (CMAKE_CXX_FLAGS_RELEASE "-O2")
     SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2")
-    SET (CMAKE_C_FLAGS "")
   ENDIF(NOT CMAKE_CXX_FLAGS)
+  IF(NOT CMAKE_C_FLAGS)
+    SET (CMAKE_C_FLAGS "")
+  ENDIF(NOT CMAKE_C_FLAGS)
 ELSE(NOT CMAKE_COMPILER_IS_GNUCXX)
   INCLUDE(${CMAKE_ROOT}/Modules/Platform/gcc.cmake)
 ENDIF(NOT CMAKE_COMPILER_IS_GNUCXX)

Modules/Platform/Windows-bcc32.cmake

@@ -55,8 +55,10 @@ IF(NOT CMAKE_CXX_FLAGS)
   SET (CMAKE_CXX_FLAGS_MINSIZEREL "-O1")
   SET (CMAKE_CXX_FLAGS_RELEASE "-O2")
   SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "-Od")
-  SET (CMAKE_C_FLAGS "-w- -whid -waus -tWM")
 ENDIF(NOT CMAKE_CXX_FLAGS)
+IF(NOT CMAKE_C_FLAGS)
+  SET (CMAKE_C_FLAGS "-w- -whid -waus -tWM")
+ENDIF(NOT CMAKE_C_FLAGS)
 
 
 SET (CMAKE_STANDARD_LIBRARIES "import32.lib" CACHE STRING 

Modules/Platform/Windows-cl.cmake

@@ -48,8 +48,10 @@ IF(NOT CMAKE_CXX_FLAGS)
   SET (CMAKE_CXX_FLAGS_MINSIZEREL "/MD /O1")
   SET (CMAKE_CXX_FLAGS_RELEASE "/MD /O2")
   SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "/MD /Zi /O2")
-  SET (CMAKE_C_FLAGS "/nologo /W3 /Zm1000")
 ENDIF(NOT CMAKE_CXX_FLAGS)
+IF(NOT CMAKE_C_FLAGS)
+  SET (CMAKE_C_FLAGS "/nologo /W3 /Zm1000")
+ENDIF(NOT CMAKE_C_FLAGS)
 
 
 SET (CMAKE_STANDARD_LIBRARIES "kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib  kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib" CACHE STRING 

Modules/Platform/gcc.cmake

@@ -4,5 +4,8 @@ IF(NOT CMAKE_CXX_FLAGS)
   SET (CMAKE_CXX_FLAGS_MINSIZEREL "-O3")
   SET (CMAKE_CXX_FLAGS_RELEASE "-O2")
   SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")
-  SET (CMAKE_C_FLAGS "")
 ENDIF(NOT CMAKE_CXX_FLAGS)
+
+IF(NOT CMAKE_C_FLAGS)
+  SET (CMAKE_C_FLAGS "")
+ENDIF(NOT CMAKE_C_FLAGS)