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| <a name="Types-for-C_002b_002b-1"></a> |
| <h4 class="subsection">10.10.1 Types for C++</h4> |
| <a name="index-UNKNOWN_005fTYPE-1"></a> |
| <a name="index-TYPENAME_005fTYPE"></a> |
| <a name="index-TYPEOF_005fTYPE"></a> |
| <a name="index-cp_005ftype_005fquals"></a> |
| <a name="index-TYPE_005fUNQUALIFIED-1"></a> |
| <a name="index-TYPE_005fQUAL_005fCONST-1"></a> |
| <a name="index-TYPE_005fQUAL_005fVOLATILE-1"></a> |
| <a name="index-TYPE_005fQUAL_005fRESTRICT-1"></a> |
| <a name="index-TYPE_005fMAIN_005fVARIANT-2"></a> |
| <a name="index-qualified-type-1"></a> |
| <a name="index-TYPE_005fSIZE-2"></a> |
| <a name="index-TYPE_005fALIGN-2"></a> |
| <a name="index-TYPE_005fPRECISION-1"></a> |
| <a name="index-TYPE_005fARG_005fTYPES-1"></a> |
| <a name="index-TYPE_005fMETHOD_005fBASETYPE-1"></a> |
| <a name="index-TYPE_005fPTRDATAMEM_005fP"></a> |
| <a name="index-TYPE_005fOFFSET_005fBASETYPE-1"></a> |
| <a name="index-TREE_005fTYPE-6"></a> |
| <a name="index-TYPE_005fCONTEXT-1"></a> |
| <a name="index-TYPE_005fNAME-2"></a> |
| <a name="index-TYPENAME_005fTYPE_005fFULLNAME-1"></a> |
| <a name="index-TYPE_005fFIELDS-1"></a> |
| <a name="index-TYPE_005fPTROBV_005fP"></a> |
| |
| <p>In C++, an array type is not qualified; rather the type of the array |
| elements is qualified. This situation is reflected in the intermediate |
| representation. The macros described here will always examine the |
| qualification of the underlying element type when applied to an array |
| type. (If the element type is itself an array, then the recursion |
| continues until a non-array type is found, and the qualification of this |
| type is examined.) So, for example, <code>CP_TYPE_CONST_P</code> will hold of |
| the type <code>const int ()[7]</code>, denoting an array of seven <code>int</code>s. |
| </p> |
| <p>The following functions and macros deal with cv-qualification of types: |
| </p><dl compact="compact"> |
| <dt><code>cp_type_quals</code> |
| <a name="index-cp_005ftype_005fquals-1"></a> |
| </dt> |
| <dd><p>This function returns the set of type qualifiers applied to this type. |
| This value is <code>TYPE_UNQUALIFIED</code> if no qualifiers have been |
| applied. The <code>TYPE_QUAL_CONST</code> bit is set if the type is |
| <code>const</code>-qualified. The <code>TYPE_QUAL_VOLATILE</code> bit is set if the |
| type is <code>volatile</code>-qualified. The <code>TYPE_QUAL_RESTRICT</code> bit is |
| set if the type is <code>restrict</code>-qualified. |
| </p> |
| </dd> |
| <dt><code>CP_TYPE_CONST_P</code> |
| <a name="index-CP_005fTYPE_005fCONST_005fP"></a> |
| </dt> |
| <dd><p>This macro holds if the type is <code>const</code>-qualified. |
| </p> |
| </dd> |
| <dt><code>CP_TYPE_VOLATILE_P</code> |
| <a name="index-CP_005fTYPE_005fVOLATILE_005fP"></a> |
| </dt> |
| <dd><p>This macro holds if the type is <code>volatile</code>-qualified. |
| </p> |
| </dd> |
| <dt><code>CP_TYPE_RESTRICT_P</code> |
| <a name="index-CP_005fTYPE_005fRESTRICT_005fP"></a> |
| </dt> |
| <dd><p>This macro holds if the type is <code>restrict</code>-qualified. |
| </p> |
| </dd> |
| <dt><code>CP_TYPE_CONST_NON_VOLATILE_P</code> |
| <a name="index-CP_005fTYPE_005fCONST_005fNON_005fVOLATILE_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds for a type that is <code>const</code>-qualified, but |
| <em>not</em> <code>volatile</code>-qualified; other cv-qualifiers are ignored as |
| well: only the <code>const</code>-ness is tested. |
| </p> |
| </dd> |
| </dl> |
| |
| <p>A few other macros and functions are usable with all types: |
| </p><dl compact="compact"> |
| <dt><code>TYPE_SIZE</code> |
| <a name="index-TYPE_005fSIZE-3"></a> |
| </dt> |
| <dd><p>The number of bits required to represent the type, represented as an |
| <code>INTEGER_CST</code>. For an incomplete type, <code>TYPE_SIZE</code> will be |
| <code>NULL_TREE</code>. |
| </p> |
| </dd> |
| <dt><code>TYPE_ALIGN</code> |
| <a name="index-TYPE_005fALIGN-3"></a> |
| </dt> |
| <dd><p>The alignment of the type, in bits, represented as an <code>int</code>. |
| </p> |
| </dd> |
| <dt><code>TYPE_NAME</code> |
| <a name="index-TYPE_005fNAME-3"></a> |
| </dt> |
| <dd><p>This macro returns a declaration (in the form of a <code>TYPE_DECL</code>) for |
| the type. (Note this macro does <em>not</em> return an |
| <code>IDENTIFIER_NODE</code>, as you might expect, given its name!) You can |
| look at the <code>DECL_NAME</code> of the <code>TYPE_DECL</code> to obtain the |
| actual name of the type. The <code>TYPE_NAME</code> will be <code>NULL_TREE</code> |
| for a type that is not a built-in type, the result of a typedef, or a |
| named class type. |
| </p> |
| </dd> |
| <dt><code>CP_INTEGRAL_TYPE</code> |
| <a name="index-CP_005fINTEGRAL_005fTYPE"></a> |
| </dt> |
| <dd><p>This predicate holds if the type is an integral type. Notice that in |
| C++, enumerations are <em>not</em> integral types. |
| </p> |
| </dd> |
| <dt><code>ARITHMETIC_TYPE_P</code> |
| <a name="index-ARITHMETIC_005fTYPE_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds if the type is an integral type (in the C++ sense) |
| or a floating point type. |
| </p> |
| </dd> |
| <dt><code>CLASS_TYPE_P</code> |
| <a name="index-CLASS_005fTYPE_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds for a class-type. |
| </p> |
| </dd> |
| <dt><code>TYPE_BUILT_IN</code> |
| <a name="index-TYPE_005fBUILT_005fIN"></a> |
| </dt> |
| <dd><p>This predicate holds for a built-in type. |
| </p> |
| </dd> |
| <dt><code>TYPE_PTRDATAMEM_P</code> |
| <a name="index-TYPE_005fPTRDATAMEM_005fP-1"></a> |
| </dt> |
| <dd><p>This predicate holds if the type is a pointer to data member. |
| </p> |
| </dd> |
| <dt><code>TYPE_PTR_P</code> |
| <a name="index-TYPE_005fPTR_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds if the type is a pointer type, and the pointee is |
| not a data member. |
| </p> |
| </dd> |
| <dt><code>TYPE_PTRFN_P</code> |
| <a name="index-TYPE_005fPTRFN_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds for a pointer to function type. |
| </p> |
| </dd> |
| <dt><code>TYPE_PTROB_P</code> |
| <a name="index-TYPE_005fPTROB_005fP"></a> |
| </dt> |
| <dd><p>This predicate holds for a pointer to object type. Note however that it |
| does not hold for the generic pointer to object type <code>void *</code>. You |
| may use <code>TYPE_PTROBV_P</code> to test for a pointer to object type as |
| well as <code>void *</code>. |
| </p> |
| </dd> |
| </dl> |
| |
| <p>The table below describes types specific to C and C++ as well as |
| language-dependent info about GENERIC types. |
| </p> |
| <dl compact="compact"> |
| <dt><code>POINTER_TYPE</code></dt> |
| <dd><p>Used to represent pointer types, and pointer to data member types. If |
| <code>TREE_TYPE</code> |
| is a pointer to data member type, then <code>TYPE_PTRDATAMEM_P</code> will hold. |
| For a pointer to data member type of the form ‘<samp>T X::*</samp>’, |
| <code>TYPE_PTRMEM_CLASS_TYPE</code> will be the type <code>X</code>, while |
| <code>TYPE_PTRMEM_POINTED_TO_TYPE</code> will be the type <code>T</code>. |
| </p> |
| </dd> |
| <dt><code>RECORD_TYPE</code></dt> |
| <dd><p>Used to represent <code>struct</code> and <code>class</code> types in C and C++. If |
| <code>TYPE_PTRMEMFUNC_P</code> holds, then this type is a pointer-to-member |
| type. In that case, the <code>TYPE_PTRMEMFUNC_FN_TYPE</code> is a |
| <code>POINTER_TYPE</code> pointing to a <code>METHOD_TYPE</code>. The |
| <code>METHOD_TYPE</code> is the type of a function pointed to by the |
| pointer-to-member function. If <code>TYPE_PTRMEMFUNC_P</code> does not hold, |
| this type is a class type. For more information, see <a href="Classes.html#Classes">Classes</a>. |
| </p> |
| </dd> |
| <dt><code>UNKNOWN_TYPE</code></dt> |
| <dd><p>This node is used to represent a type the knowledge of which is |
| insufficient for a sound processing. |
| </p> |
| </dd> |
| <dt><code>TYPENAME_TYPE</code></dt> |
| <dd><p>Used to represent a construct of the form <code>typename T::A</code>. The |
| <code>TYPE_CONTEXT</code> is <code>T</code>; the <code>TYPE_NAME</code> is an |
| <code>IDENTIFIER_NODE</code> for <code>A</code>. If the type is specified via a |
| template-id, then <code>TYPENAME_TYPE_FULLNAME</code> yields a |
| <code>TEMPLATE_ID_EXPR</code>. The <code>TREE_TYPE</code> is non-<code>NULL</code> if the |
| node is implicitly generated in support for the implicit typename |
| extension; in which case the <code>TREE_TYPE</code> is a type node for the |
| base-class. |
| </p> |
| </dd> |
| <dt><code>TYPEOF_TYPE</code></dt> |
| <dd><p>Used to represent the <code>__typeof__</code> extension. The |
| <code>TYPE_FIELDS</code> is the expression the type of which is being |
| represented. |
| </p> |
| </dd> |
| </dl> |
| |
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