Fail with #error early if the compiler does not support bool or explicit.

The fail mode for bool is moved from later in qglobal.h, and explicit is
used unguarded throughout Qt, so the macro is already useless.

Change-Id: Iff26892b025ba155e360a1f2dc93a67a6622dbc1
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/global/qcompilerdetection.h

@@ -76,7 +76,7 @@
 #  define Q_CC_SYM
 /* "explicit" semantics implemented in 8.1e but keyword recognized since 7.5 */
 #  if defined(__SC__) && __SC__ < 0x750
-#    define Q_NO_EXPLICIT_KEYWORD
+#    error "Compiler not supported"
 #  endif
 #  define Q_NO_USING_KEYWORD
 
@@ -114,8 +114,7 @@
 #  define Q_CC_BOR
 #  define Q_INLINE_TEMPLATE
 #  if __BORLANDC__ < 0x502
-#    define Q_NO_BOOL_TYPE
-#    define Q_NO_EXPLICIT_KEYWORD
+#    error "Compiler not supported"
 #  endif
 #  define Q_NO_USING_KEYWORD
 
@@ -251,12 +250,7 @@
 #  define Q_CC_XLC
 #  define Q_FULL_TEMPLATE_INSTANTIATION
 #  if __xlC__ < 0x400
-#    define Q_NO_BOOL_TYPE
-#    define Q_NO_EXPLICIT_KEYWORD
-#    define Q_NO_USING_KEYWORD
-#    define Q_OUTOFLINE_TEMPLATE inline
-#    define Q_BROKEN_TEMPLATE_SPECIALIZATION
-#    define Q_CANNOT_DELETE_CONSTANT
+#    error "Compiler not supported"
 #  elif __xlC__ >= 0x0600
 #    define Q_ALIGNOF(type)     __alignof__(type)
 #    define Q_TYPEOF(expr)      __typeof__(expr)
@@ -280,7 +274,7 @@
    - observed on Compaq C++ V6.3-002.
    In any case versions prior to Compaq C++ V6.0-005 do not have bool. */
 #  if !defined(_BOOL_EXISTS)
-#    define Q_NO_BOOL_TYPE
+#    error "Compiler not supported"
 #  endif
 /* Spurious (?) error messages observed on Compaq C++ V6.5-014. */
 #  define Q_NO_USING_KEYWORD
@@ -315,7 +309,7 @@
    __BOOL_DEFINED
         Defined in Microsoft C++ mode when bool is a keyword. */
 #  if !defined(_BOOL) && !defined(__BOOL_DEFINED)
-#    define Q_NO_BOOL_TYPE
+#    error "Compiler not supported"
 #  endif
 
 /* The Comeau compiler is based on EDG and does define __EDG__ */
@@ -341,9 +335,8 @@
 
 #  elif defined(__DCC__)
 #    define Q_CC_DIAB
-#    undef Q_NO_BOOL_TYPE
 #    if !defined(__bool)
-#      define Q_NO_BOOL_TYPE
+#      error "Compiler not supported"
 #    endif
 
 /* The UnixWare 7 UDK compiler is based on EDG and does define __EDG__ */
@@ -407,7 +400,7 @@
 #      define Q_NO_TEMPLATE_FRIENDS
 #    endif
 #    if !defined(_BOOL)
-#      define Q_NO_BOOL_TYPE
+#      error "Compiler not supported"
 #    endif
 #    if defined(__SUNPRO_CC_COMPAT) && (__SUNPRO_CC_COMPAT <= 4)
 #      define Q_NO_USING_KEYWORD
@@ -415,9 +408,7 @@
 #    define Q_C_CALLBACKS
 /* 4.2 compiler or older */
 #  else
-#    define Q_NO_BOOL_TYPE
-#    define Q_NO_EXPLICIT_KEYWORD
-#    define Q_NO_USING_KEYWORD
+#    error "Compiler not supported"
 #  endif
 
 /* CDS++ does not seem to define __EDG__ or __EDG according to Reliant
@@ -426,7 +417,7 @@
 #  define Q_CC_EDG
 #  define Q_CC_CDS
 #  if !defined(_BOOL)
-#    define Q_NO_BOOL_TYPE
+#    error "Compiler not supported"
 #  endif
 #  define Q_BROKEN_TEMPLATE_SPECIALIZATION
 
@@ -449,11 +440,7 @@
 #      define Q_DECL_IMPORT     Q_DECL_EXPORT
 #    endif
 #  else
-#    define Q_CC_HP
-#    define Q_NO_BOOL_TYPE
-#    define Q_FULL_TEMPLATE_INSTANTIATION
-#    define Q_BROKEN_TEMPLATE_SPECIALIZATION
-#    define Q_NO_EXPLICIT_KEYWORD
+#    error "Compiler not supported"
 #  endif
 #  define Q_NO_USING_KEYWORD /* ### check "using" status */
 

src/corelib/global/qglobal.h

@@ -275,11 +275,6 @@ typedef unsigned int uint;
 typedef unsigned long ulong;
 QT_END_INCLUDE_NAMESPACE
 
-#if defined(Q_NO_BOOL_TYPE)
-#error "Compiler doesn't support the bool type"
-#endif
-
-
 /*
    Constant bool values
 */