Merge pull request #3074 from matt-gretton-dann/codeql-c-extractor/50-char8_t

Add support for C++20's char8_t type.

Author: nickrolfe

cpp/ql/src/semmle/code/cpp/Type.qll

@@ -376,6 +376,8 @@ private predicate isIntegralType(@builtintype type, int kind) {
     kind = 43
     or
     kind = 44
+    or
+    kind = 51
   )
 }
 
@@ -463,6 +465,8 @@ private predicate integralTypeMapping(int original, int canonical, int unsigned,
   original = 43 and canonical = 43 and unsigned = -1 and signed = -1 // char16_t
   or
   original = 44 and canonical = 44 and unsigned = -1 and signed = -1 // char32_t
+  or
+  original = 51 and canonical = 51 and unsigned = -1 and signed = -1 // char8_t
 }
 
 /**
@@ -993,6 +997,18 @@ class WideCharType extends IntegralType {
   override string getCanonicalQLClass() { result = "WideCharType" }
 }
 
+/**
+ * The C/C++ `char8_t` type.  This is available starting with C++20.
+ * ```
+ * char8_t c8;
+ * ```
+ */
+class Char8Type extends IntegralType {
+  Char8Type() { builtintypes(underlyingElement(this), _, 51, _, _, _) }
+
+  override string getCanonicalQLClass() { result = "Char8Type" }
+}
+
 /**
  * The C/C++ `char16_t` type.  This is available starting with C11 and C++11.
  * ```

cpp/ql/src/semmle/code/cpp/padding/Padding.qll

@@ -74,6 +74,8 @@ abstract class Architecture extends string {
     or
     t instanceof WideCharType and result = wideCharSize()
     or
+    t instanceof Char8Type and result = 8
+    or
     t instanceof Char16Type and result = 16
     or
     t instanceof Char32Type and result = 32
@@ -155,6 +157,8 @@ abstract class Architecture extends string {
     or
     t instanceof WideCharType and result = wideCharSize()
     or
+    t instanceof Char8Type and result = 8
+    or
     t instanceof Char16Type and result = 16
     or
     t instanceof Char32Type and result = 32

cpp/ql/src/semmlecode.cpp.dbscheme

@@ -616,6 +616,7 @@ enumconstants(
   | 48 = _Float64x
   | 49 = _Float128
   | 50 = _Float128x
+  | 51 = char8_t
   ;
 */
 builtintypes(

cpp/ql/test/library-tests/clang_ms/element.expected

@@ -61,6 +61,7 @@
 | file://:0:0:0:0 | auto |
 | file://:0:0:0:0 | bool |
 | file://:0:0:0:0 | char |
+| file://:0:0:0:0 | char8_t |
 | file://:0:0:0:0 | char16_t |
 | file://:0:0:0:0 | char32_t |
 | file://:0:0:0:0 | const |

cpp/ql/test/library-tests/conditions/elements.expected

@@ -38,6 +38,7 @@
 | file://:0:0:0:0 | auto |
 | file://:0:0:0:0 | bool |
 | file://:0:0:0:0 | char |
+| file://:0:0:0:0 | char8_t |
 | file://:0:0:0:0 | char16_t |
 | file://:0:0:0:0 | char32_t |
 | file://:0:0:0:0 | const |

cpp/ql/test/library-tests/templates/instantiations_functions/elements.expected

@@ -51,6 +51,7 @@
 | file://:0:0:0:0 | auto |
 | file://:0:0:0:0 | bool |
 | file://:0:0:0:0 | char |
+| file://:0:0:0:0 | char8_t |
 | file://:0:0:0:0 | char16_t |
 | file://:0:0:0:0 | char32_t |
 | file://:0:0:0:0 | composite<int> & |

cpp/ql/test/library-tests/templates/type_instantiations/types.expected

@@ -23,6 +23,7 @@
 | file://:0:0:0:0 | auto |
 | file://:0:0:0:0 | bool |
 | file://:0:0:0:0 | char |
+| file://:0:0:0:0 | char8_t |
 | file://:0:0:0:0 | char16_t |
 | file://:0:0:0:0 | char32_t |
 | file://:0:0:0:0 | const __va_list_tag |

cpp/ql/test/library-tests/type_sizes/type_sizes.expected

@@ -44,6 +44,7 @@
 | file://:0:0:0:0 | auto | <none> |
 | file://:0:0:0:0 | bool | 1 |
 | file://:0:0:0:0 | char | 1 |
+| file://:0:0:0:0 | char8_t | 1 |
 | file://:0:0:0:0 | char16_t | 2 |
 | file://:0:0:0:0 | char32_t | 4 |
 | file://:0:0:0:0 | char * | 8 |

cpp/ql/test/library-tests/types/integral_types/integral_type.expected

@@ -20,3 +20,4 @@
 | 37 | signed __int128    | signed | -------- | explicitlySigned | ------------------ | ---------------- | 16 | 16 | unsigned __int128 |  |
 | 43 | char16_t           | ------ | -------- | ---------------- | ------------------ | ---------------- | 2 | 2 | <no unsigned equivalent> |  |
 | 44 | char32_t           | ------ | -------- | ---------------- | ------------------ | ---------------- | 4 | 4 | <no unsigned equivalent> |  |
+| 51 | char8_t            | ------ | -------- | ---------------- | ------------------ | ---------------- | 1 | 1 | <no unsigned equivalent> |  |

cpp/ql/test/library-tests/types/integral_types_ms/integral_type.expected

@@ -20,3 +20,4 @@
 | 37 | signed __int128    | signed | -------- | explicitlySigned | ------------------ | ---------------- | 16 | 16 | unsigned __int128 |  |
 | 43 | char16_t           | ------ | -------- | ---------------- | ------------------ | ---------------- | 2 | 2 | <no unsigned equivalent> |  |
 | 44 | char32_t           | ------ | -------- | ---------------- | ------------------ | ---------------- | 4 | 4 | <no unsigned equivalent> |  |
+| 51 | char8_t            | ------ | -------- | ---------------- | ------------------ | ---------------- | 1 | 1 | <no unsigned equivalent> |  |