-Attributes such as those shown below, are not yet supported and will give a syntax error. +Attributes such as those shown below, are supported since SWIG 4.1.0 but are +currently crudely ignored by the parser's tokeniser so they have no effect on +SWIG's code generation.
diff --git a/Examples/test-suite/common.mk b/Examples/test-suite/common.mk
index bf0e52f02..c654807d7 100644
--- a/Examples/test-suite/common.mk
+++ b/Examples/test-suite/common.mk
@@ -583,6 +583,7 @@ CPP11_TEST_CASES += \
cpp11_alias_nested_template_scoping \
cpp11_alignment \
cpp11_alternate_function_syntax \
+ cpp11_attribute_specifiers \
cpp11_constexpr \
cpp11_decltype \
cpp11_default_delete \
diff --git a/Examples/test-suite/cpp11_attribute_specifiers.i b/Examples/test-suite/cpp11_attribute_specifiers.i
new file mode 100644
index 000000000..063e431e0
--- /dev/null
+++ b/Examples/test-suite/cpp11_attribute_specifiers.i
@@ -0,0 +1,50 @@
+%module cpp11_attribute_specifiers
+
+%inline %{
+
+#if defined(__GNUC__)
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations" // We're using a deprecated attribute here...
+#pragma GCC diagnostic ignored "-Wattributes" // likely is C++20
+#pragma GCC diagnostic ignored "-Wunused-variable" // We are using an unused variable on purpose here
+#pragma GCC diagnostic ignored "-Wunused-parameter" // We are using an unused param on purpose here
+#endif
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#pragma clang diagnostic ignored "-Wattributes"
+#pragma clang diagnostic ignored "-Wunused-variable"
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+
+
+[[noreturn]] void noReturn() { throw; }
+[[nodiscard]] bool noDiscard() { return true; }
+[[nodiscard, deprecated("This has been replaced")]] bool noDiscardDeprecated() { return true; }
+void maybeUnused1([[maybe_unused]] bool b) { }
+bool maybeUnused2(bool a, [[maybe_unused]] bool b) { return a; }
+
+[[deprecated, nodiscard]] bool likely([[maybe_unused]] bool a, bool b) {
+ [[maybe_unused]] bool c = b;
+ if (b) [[likely]] {
+ return true;
+ } else [[unlikely]] {
+ if(a) {
+ return true;
+ }
+ }
+ return false;
+}
+
+struct [[nodiscard]] S { };
+
+const char *test_string_literal() { return "Test [[ and ]] in string literal"; }
+
+#if 0
+// Check that SWIG doesn't choke on ]] when it's not part of an attribute.
+// FIXME: SWIG's parser doesn't handle this case currently.
+int *a;
+int b = a[a[0]];
+#endif
+
+%}
diff --git a/Examples/test-suite/php/cpp11_attribute_specifiers_runme.php b/Examples/test-suite/php/cpp11_attribute_specifiers_runme.php
new file mode 100644
index 000000000..2336b319a
--- /dev/null
+++ b/Examples/test-suite/php/cpp11_attribute_specifiers_runme.php
@@ -0,0 +1,14 @@
+ 0));
+ if (tok <= 0) {
+ Swig_error(cparse_file, cparse_line, "Unbalanced double brackets, missing closing (']]'). Reached end of input.\n");
+ }
+ break;
+
+ case SWIG_TOKEN_RRBRACKET:
+ /* Turn an unmatched ]] back into two ] - e.g. `a[a[0]]` */
+ scanner_next_token(RBRACKET);
+ return RBRACKET;
+
/* Look for multi-character sequences */
case SWIG_TOKEN_RSTRING:
diff --git a/Source/Swig/scanner.c b/Source/Swig/scanner.c
index 65f534a79..b03a07a5b 100644
--- a/Source/Swig/scanner.c
+++ b/Source/Swig/scanner.c
@@ -596,10 +596,6 @@ static int look(Scanner *s) {
state = 3;
else if (c == '\\')
return SWIG_TOKEN_BACKSLASH;
- else if (c == '[')
- return SWIG_TOKEN_LBRACKET;
- else if (c == ']')
- return SWIG_TOKEN_RBRACKET;
else if (c == '@')
return SWIG_TOKEN_AT;
else if (c == '$')
@@ -637,6 +633,10 @@ static int look(Scanner *s) {
else if (c == '.')
state = 100; /* Maybe a number, maybe ellipsis, just a period */
+ else if (c == '[')
+ state = 102; /* Maybe a bracket or a double bracket */
+ else if (c == ']')
+ state = 103; /* Maybe a bracket or a double bracket */
else if (isdigit(c))
state = 8; /* A numerical value */
else
@@ -1358,6 +1358,31 @@ static int look(Scanner *s) {
}
break;
+ /* A left bracket or a double left bracket */
+ case 102:
+
+ if ((c = nextchar(s)) == 0) {
+ return SWIG_TOKEN_LBRACKET;
+ } else if (c == '[') {
+ return SWIG_TOKEN_LLBRACKET;
+ } else {
+ retract(s, 1);
+ return SWIG_TOKEN_LBRACKET;
+ }
+ break;
+
+ /* a right bracket or a double right bracket */
+ case 103:
+ if ((c = nextchar(s)) == 0) {
+ return SWIG_TOKEN_RBRACKET;
+ } else if (c == ']') {
+ return SWIG_TOKEN_RRBRACKET;
+ } else {
+ retract(s, 1);
+ return SWIG_TOKEN_RBRACKET;
+ }
+ break;
+
case 200: /* PLUS, PLUSPLUS, PLUSEQUAL */
if ((c = nextchar(s)) == 0)
return SWIG_TOKEN_PLUS;
diff --git a/Source/Swig/swigscan.h b/Source/Swig/swigscan.h
index 4f66de8a2..526413a14 100644
--- a/Source/Swig/swigscan.h
+++ b/Source/Swig/swigscan.h
@@ -71,6 +71,8 @@ extern void Scanner_locator(Scanner *, String *loc);
#define SWIG_TOKEN_WSTRING 33 /* L"str" */
#define SWIG_TOKEN_WCHAR 34 /* L'c' */
#define SWIG_TOKEN_ELLIPSIS 35 /* ... */
+#define SWIG_TOKEN_LLBRACKET 36 /* [[ */
+#define SWIG_TOKEN_RRBRACKET 37 /* ]] */
#define SWIG_TOKEN_ILLEGAL 99
#define SWIG_TOKEN_ERROR -1