c, libcpp: Partially implement C2Y N3353 paper [PR117028]

The following patch partially implements the N3353 paper.
In particular, it adds support for the delimited escape sequences
(\u{123}, \x{123}, \o{123}) which were added already for C++23,
all I had to do is split the delimited escape sequence guarding from
named universal character escape sequence guards
(\N{LATIN CAPITAL LETTER C WITH CARON}), which C++23 has but C2Y doesn't
and emit different diagnostics for C from C++ for the delimited escape
sequences.
And it adds support for the new style of octal literals, 0o137 or 0O1777.
I have so far added that just for C and not C++, because I have no idea
whether C++ will want to handle it similarly.

What the patch doesn't do is any kind of diagnostics for obsoletion of
\137 or 0137, as discussed in the PR, I think it is way too early for that.
Perhaps some non-default warning later on.

2024-10-17  Jakub Jelinek  <jakub@redhat.com>

	PR c/117028
libcpp/
	* include/cpplib.h (struct cpp_options): Add named_uc_escape_seqs,
	octal_constants and cpp_warn_c23_c2y_compat members.
	(enum cpp_warning_reason): Add CPP_W_C23_C2Y_COMPAT enumerator.
	* init.cc (struct lang_flags): Add named_uc_escape_seqs and
	octal_constants bit-fields.
	(lang_defaults): Add initializers for them into the table.
	(cpp_set_lang): Initialize named_uc_escape_seqs and octal_constants.
	(cpp_create_reader): Initialize cpp_warn_c23_c2y_compat to -1.
	* charset.cc (_cpp_valid_ucn): Test
	CPP_OPTION (pfile, named_uc_escape_seqs) rather than
	CPP_OPTION (pfile, delimited_escape_seqs) in \N{} related tests.
	Change wording of C cpp_pedwarning for \u{} and emit
	-Wc23-c2y-compat warning for it too if needed.  Formatting fixes.
	(convert_hex): Change wording of C cpp_pedwarning for \u{} and emit
	-Wc23-c2y-compat warning for it too if needed.
	(convert_oct): Likewise.
	* expr.cc (cpp_classify_number): Handle C2Y 0o or 0O prefixed
	octal constants.
	(cpp_interpret_integer): Likewise.
gcc/c-family/
	* c.opt (Wc23-c2y-compat): Add CPP and CppReason parameters.
	* c-opts.cc (set_std_c2y): Use CLK_STDC2Y or CLK_GNUC2Y rather
	than CLK_STDC23 and CLK_GNUC23.  Formatting fix.
	* c-lex.cc (interpret_integer): Handle C2Y 0o or 0O prefixed
	and wb/WB/uwb/UWB suffixed octal constants.
gcc/testsuite/
	* gcc.dg/bitint-112.c: New test.
	* gcc.dg/c23-digit-separators-1.c: Add _Static_assert for
	valid binary constant with digit separator.
	* gcc.dg/c23-octal-constants-1.c: New test.
	* gcc.dg/c23-octal-constants-2.c: New test.
	* gcc.dg/c2y-digit-separators-1.c: New test.
	* gcc.dg/c2y-digit-separators-2.c: New test.
	* gcc.dg/c2y-octal-constants-1.c: New test.
	* gcc.dg/c2y-octal-constants-2.c: New test.
	* gcc.dg/c2y-octal-constants-3.c: New test.
	* gcc.dg/cpp/c23-delimited-escape-seq-1.c: New test.
	* gcc.dg/cpp/c23-delimited-escape-seq-2.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-1.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-2.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-3.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-4.c: New test.
	* gcc.dg/octal-constants-1.c: New test.
	* gcc.dg/octal-constants-2.c: New test.
	* gcc.dg/octal-constants-3.c: New test.
	* gcc.dg/octal-constants-4.c: New test.
	* gcc.dg/system-octal-constants-1.c: New test.
	* gcc.dg/system-octal-constants-1.h: New file.

24 files changed, 760 insertions, 2 deletions

diff --git a/gcc/c-family/c-lex.cc b/gcc/c-family/c-lex.cc
index fa46455..f7168ce 100644
--- a/gcc/c-family/c-lex.cc
+++ b/gcc/c-family/c-lex.cc
@@ -941,6 +941,10 @@ interpret_integer (const cpp_token *token, unsigned int flags,
 	{
 	  max_bits_per_digit = 3;
 	  prefix_len = 1;
+	  if (token->val.str.len > 2
+	      && (token->val.str.text[1] == 'o'
+		  || token->val.str.text[1] == 'O'))
+	    prefix_len = 2;
 	}
       else if ((flags & CPP_N_RADIX) == CPP_N_HEX)
 	{
diff --git a/gcc/c-family/c-opts.cc b/gcc/c-family/c-opts.cc
index 21ed7c7..afb963d 100644
--- a/gcc/c-family/c-opts.cc
+++ b/gcc/c-family/c-opts.cc
@@ -1892,7 +1892,7 @@ set_std_c23 (int iso)
 static void
 set_std_c2y (int iso)
 {
-  cpp_set_lang (parse_in, iso ? CLK_STDC23: CLK_GNUC23);
+  cpp_set_lang (parse_in, iso ? CLK_STDC2Y : CLK_GNUC2Y);
   flag_no_asm = iso;
   flag_no_nonansi_builtin = iso;
   flag_iso = iso;
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index f758d7b..d5608ec 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -452,7 +452,7 @@ C ObjC Alias(Wc11-c23-compat)
 Deprecated in favor of -Wc11-c23-compat.
 
 Wc23-c2y-compat
-C ObjC Var(warn_c23_c2y_compat) Init(-1) Warning
+C ObjC CPP(cpp_warn_c23_c2y_compat) CppReason(CPP_W_C23_C2Y_COMPAT) Var(warn_c23_c2y_compat) Init(-1) Warning
 Warn about features not present in ISO C23, but present in ISO C2Y.
 
 Wc90-c99-compat
diff --git a/gcc/testsuite/gcc.dg/bitint-112.c b/gcc/testsuite/gcc.dg/bitint-112.c
new file mode 100644
index 0000000..354dd8f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/bitint-112.c
@@ -0,0 +1,5 @@
+/* { dg-do compile { target bitint575 } } */
+/* { dg-options "-std=c2y" } */
+
+static_assert (0o177777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777wb / 2wb * 2wb + 1wb == 0x3fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffwb, "");
+static_assert (0O3211423263360473024126605062402061031423012516423720422320324010721642021266620206352436541213777372642147046071532121506001467430513304743521547653653136162305775772330633147605317353126354wb == 0x1a2626b3784ec2856c28ca04310cc4c154e89f4224d06a023a3a208adb20867547ac28bffbeb4467130e6b451a30066f18a5b13c751b3eaf565e39317fbfa6c66ccf8567bacacecwb, "");
diff --git a/gcc/testsuite/gcc.dg/c23-digit-separators-1.c b/gcc/testsuite/gcc.dg/c23-digit-separators-1.c
index 4b5f4f6..03fe1f4 100644
--- a/gcc/testsuite/gcc.dg/c23-digit-separators-1.c
+++ b/gcc/testsuite/gcc.dg/c23-digit-separators-1.c
@@ -5,6 +5,7 @@
 _Static_assert (123'45'6 == 123456);
 _Static_assert (0'123 == 0123);
 _Static_assert (0x1'23 == 0x123);
+_Static_assert (0b1'01 == 0b101);
 
 #define m(x) 0
 
diff --git a/gcc/testsuite/gcc.dg/c23-octal-constants-1.c b/gcc/testsuite/gcc.dg/c23-octal-constants-1.c
new file mode 100644
index 0000000..2696073
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c23-octal-constants-1.c
@@ -0,0 +1,11 @@
+/* Test that octal constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic" } */
+
+int a = 0o7; /* { dg-warning "'0o' prefixed constants" } */
+#if 0o107 /* { dg-warning "'0o' prefixed constants" } */
+#endif
+
+int b = 0O7; /* { dg-warning "'0o' prefixed constants" } */
+#if 0O107 /* { dg-warning "'0o' prefixed constants" } */
+#endif
diff --git a/gcc/testsuite/gcc.dg/c23-octal-constants-2.c b/gcc/testsuite/gcc.dg/c23-octal-constants-2.c
new file mode 100644
index 0000000..8ee9609
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c23-octal-constants-2.c
@@ -0,0 +1,11 @@
+/* Test that octal constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+
+int a = 0o7; /* { dg-error "'0o' prefixed constants" } */
+#if 0o107 /* { dg-error "'0o' prefixed constants" } */
+#endif
+
+int b = 0O7; /* { dg-error "'0o' prefixed constants" } */
+#if 0O107 /* { dg-error "'0o' prefixed constants" } */
+#endif
diff --git a/gcc/testsuite/gcc.dg/c2y-digit-separators-1.c b/gcc/testsuite/gcc.dg/c2y-digit-separators-1.c
new file mode 100644
index 0000000..b600328
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c2y-digit-separators-1.c
@@ -0,0 +1,6 @@
+/* Test C2Y digit separators.  Valid usages.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -pedantic-errors" } */
+
+_Static_assert (0o3'703 == 0O3703);
+_Static_assert (0O1'7'7'7 == 0o1777);
diff --git a/gcc/testsuite/gcc.dg/c2y-digit-separators-2.c b/gcc/testsuite/gcc.dg/c2y-digit-separators-2.c
new file mode 100644
index 0000000..e634c38
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c2y-digit-separators-2.c
@@ -0,0 +1,11 @@
+/* Test C2Y digit separators.  Invalid usages.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -pedantic-errors" } */
+
+void
+tf (void)
+{
+  int i;
+  i = 0o'0; /* { dg-error "digit separator after base indicator" } */
+  i = 0O'7; /* { dg-error "digit separator after base indicator" } */
+}
diff --git a/gcc/testsuite/gcc.dg/c2y-octal-constants-1.c b/gcc/testsuite/gcc.dg/c2y-octal-constants-1.c
new file mode 100644
index 0000000..9a338967
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c2y-octal-constants-1.c
@@ -0,0 +1,5 @@
+/* Test C2Y octal constants.  Valid syntax and types.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -pedantic-errors" } */
+
+#include "octal-constants-1.c"
diff --git a/gcc/testsuite/gcc.dg/c2y-octal-constants-2.c b/gcc/testsuite/gcc.dg/c2y-octal-constants-2.c
new file mode 100644
index 0000000..df29236
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c2y-octal-constants-2.c
@@ -0,0 +1,11 @@
+/* Test that octal constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+
+int a = 0o7; /* { dg-warning "C2Y feature" } */
+#if 0o107 /* { dg-warning "C2Y feature" } */
+#endif
+
+int b = 0O7; /* { dg-warning "C2Y feature" } */
+#if 0O107 /* { dg-warning "C2Y feature" } */
+#endif
diff --git a/gcc/testsuite/gcc.dg/c2y-octal-constants-3.c b/gcc/testsuite/gcc.dg/c2y-octal-constants-3.c
new file mode 100644
index 0000000..dc79739
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c2y-octal-constants-3.c
@@ -0,0 +1,9 @@
+/* Test C2Y octal constants.  Invalid constants.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -pedantic-errors" } */
+
+int a = 0o; /* { dg-error "invalid suffix" } */
+int b = 0Oa; /* { dg-error "invalid suffix" } */
+int c = 0O08; /* { dg-error "invalid digit" } */
+int d = 0o1.1; /* { dg-error "invalid prefix" } */
+int e = 0O0p0; /* { dg-error "invalid suffix" } */
diff --git a/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-1.c b/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-1.c
new file mode 100644
index 0000000..bb73e8a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-1.c
@@ -0,0 +1,87 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do compile } */
+/* { dg-require-effective-target wchar } */
+/* { dg-options "-std=c23 -pedantic -Wno-c++-compat" } */
+
+#include <wchar.h>
+typedef __CHAR16_TYPE__ char16_t;
+typedef __CHAR32_TYPE__ char32_t;
+
+const char32_t *a = U"\u{1234}\u{10fffd}\u{000000000000000000000000000000000000000000000000000000000001234}\u{10FFFD}";		/* { dg-warning "delimited escape sequences are only valid in" } */
+const char32_t *b = U"\x{1234}\x{10fffd}\x{000000000000000000000000000000000000000000000000000000000001234}";			/* { dg-warning "delimited escape sequences are only valid in" } */
+const char32_t *c = U"\o{1234}\o{4177775}\o{000000000000000000000000000000000000000000000000000000000000000000000000004177775}";/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *d = u"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *e = u"\x{1234}\x{BffD}\x{000001234}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *f = u"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *g = L"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *h = L"\x{1234}\x{bFFd}\x{000001234}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *i = L"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-warning "delimited escape sequences are only valid in" } */
+const char *k = "\x{34}\x{000000000000000003D}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const char *l = "\o{34}\o{000000000000000176}";											/* { dg-warning "delimited escape sequences are only valid in" } */
+
+#if U'\u{1234}' != U'\u1234' || U'\u{10fffd}' != U'\U0010FFFD' \
+    || U'\x{00000001234}' != U'\x1234' || U'\x{010fffd}' != U'\x10FFFD' \
+    || U'\o{1234}' != U'\x29c' || U'\o{004177775}' != U'\x10FFFD' \
+    || u'\u{1234}' != u'\u1234' || u'\u{0bffd}' != u'\uBFFD' \
+    || u'\x{00000001234}' != u'\x1234' || u'\x{0Bffd}' != u'\x0bFFD' \
+    || u'\o{1234}' != u'\x29c' || u'\o{00137775}' != u'\xBFFD' \
+    || L'\u{1234}' != L'\u1234' || L'\u{0bffd}' != L'\uBFFD' \
+    || L'\x{00000001234}' != L'\x1234' || L'\x{0bffd}' != L'\x0bFFD' \
+    || L'\o{1234}' != L'\x29c' || L'\o{00137775}' != L'\xBFFD' \
+    || '\x{34}' != '\x034' || '\x{0003d}' != '\x003D' \
+    || '\o{34}' != '\x1C' || '\o{176}' != '\x007E'
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+#error Bad
+#endif
+
+int
+main ()
+{
+  if (a[0] != U'\u1234' || a[0] != U'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || a[1] != U'\U0010FFFD' || a[1] != U'\u{000010fFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || a[2] != a[0]
+      || a[3] != a[1]
+      || b[0] != U'\x1234' || b[0] != U'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || b[1] != U'\x10FFFD' || b[1] != U'\x{0010fFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || b[2] != b[0]
+      || c[0] != U'\x29c' || c[0] != U'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || c[1] != U'\x10FFFD' || c[1] != U'\o{4177775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || c[2] != c[1])
+    __builtin_abort ();
+  if (d[0] != u'\u1234' || d[0] != u'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || d[1] != u'\U0000BFFD' || d[1] != u'\u{00000bFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || d[2] != d[0]
+      || e[0] != u'\x1234' || e[0] != u'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || e[1] != u'\xBFFD' || e[1] != u'\x{00bFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || e[2] != e[0]
+      || f[0] != u'\x29c' || f[0] != u'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || f[1] != u'\xbFFD' || f[1] != u'\o{137775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || f[2] != f[1])
+    __builtin_abort ();
+  if (g[0] != L'\u1234' || g[0] != L'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || g[1] != L'\U0000BFFD' || g[1] != L'\u{00000bFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || g[2] != g[0]
+      || h[0] != L'\x1234' || h[0] != L'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || h[1] != L'\xBFFD' || h[1] != L'\x{00bFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || h[2] != h[0]
+      || i[0] != L'\x29c' || i[0] != L'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || i[1] != L'\xbFFD' || i[1] != L'\o{137775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || i[2] != i[1])
+    __builtin_abort ();
+  if (k[0] != '\x034' || k[0] != '\x{0034}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || k[1] != '\x3D' || k[1] != '\x{3d}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || l[0] != '\x1c' || l[0] != '\o{0034}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || l[1] != '\x07e' || l[1] != '\o{176}' || l[1] != '\176')		/* { dg-warning "delimited escape sequences are only valid in" } */
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-2.c b/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-2.c
new file mode 100644
index 0000000..04a5243
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c23-delimited-escape-seq-2.c
@@ -0,0 +1,87 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do compile } */
+/* { dg-require-effective-target wchar } */
+/* { dg-options "-std=c23 -pedantic-errors -Wno-c++-compat" } */
+
+#include <wchar.h>
+typedef __CHAR16_TYPE__ char16_t;
+typedef __CHAR32_TYPE__ char32_t;
+
+const char32_t *a = U"\u{1234}\u{10fffd}\u{000000000000000000000000000000000000000000000000000000000001234}\u{10FFFD}";		/* { dg-error "delimited escape sequences are only valid in" } */
+const char32_t *b = U"\x{1234}\x{10fffd}\x{000000000000000000000000000000000000000000000000000000000001234}";			/* { dg-error "delimited escape sequences are only valid in" } */
+const char32_t *c = U"\o{1234}\o{4177775}\o{000000000000000000000000000000000000000000000000000000000000000000000000004177775}";/* { dg-error "delimited escape sequences are only valid in" } */
+const char16_t *d = u"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-error "delimited escape sequences are only valid in" } */
+const char16_t *e = u"\x{1234}\x{BffD}\x{000001234}";										/* { dg-error "delimited escape sequences are only valid in" } */
+const char16_t *f = u"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-error "delimited escape sequences are only valid in" } */
+const wchar_t *g = L"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-error "delimited escape sequences are only valid in" } */
+const wchar_t *h = L"\x{1234}\x{bFFd}\x{000001234}";										/* { dg-error "delimited escape sequences are only valid in" } */
+const wchar_t *i = L"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-error "delimited escape sequences are only valid in" } */
+const char *k = "\x{34}\x{000000000000000003D}";										/* { dg-error "delimited escape sequences are only valid in" } */
+const char *l = "\o{34}\o{000000000000000176}";											/* { dg-error "delimited escape sequences are only valid in" } */
+
+#if U'\u{1234}' != U'\u1234' || U'\u{10fffd}' != U'\U0010FFFD' \
+    || U'\x{00000001234}' != U'\x1234' || U'\x{010fffd}' != U'\x10FFFD' \
+    || U'\o{1234}' != U'\x29c' || U'\o{004177775}' != U'\x10FFFD' \
+    || u'\u{1234}' != u'\u1234' || u'\u{0bffd}' != u'\uBFFD' \
+    || u'\x{00000001234}' != u'\x1234' || u'\x{0Bffd}' != u'\x0bFFD' \
+    || u'\o{1234}' != u'\x29c' || u'\o{00137775}' != u'\xBFFD' \
+    || L'\u{1234}' != L'\u1234' || L'\u{0bffd}' != L'\uBFFD' \
+    || L'\x{00000001234}' != L'\x1234' || L'\x{0bffd}' != L'\x0bFFD' \
+    || L'\o{1234}' != L'\x29c' || L'\o{00137775}' != L'\xBFFD' \
+    || '\x{34}' != '\x034' || '\x{0003d}' != '\x003D' \
+    || '\o{34}' != '\x1C' || '\o{176}' != '\x007E'
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-error "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+#error Bad
+#endif
+
+int
+main ()
+{
+  if (a[0] != U'\u1234' || a[0] != U'\u{1234}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || a[1] != U'\U0010FFFD' || a[1] != U'\u{000010fFfD}'			/* { dg-error "delimited escape sequences are only valid in" } */
+      || a[2] != a[0]
+      || a[3] != a[1]
+      || b[0] != U'\x1234' || b[0] != U'\x{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || b[1] != U'\x10FFFD' || b[1] != U'\x{0010fFfD}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || b[2] != b[0]
+      || c[0] != U'\x29c' || c[0] != U'\o{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || c[1] != U'\x10FFFD' || c[1] != U'\o{4177775}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || c[2] != c[1])
+    __builtin_abort ();
+  if (d[0] != u'\u1234' || d[0] != u'\u{1234}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || d[1] != u'\U0000BFFD' || d[1] != u'\u{00000bFfD}'			/* { dg-error "delimited escape sequences are only valid in" } */
+      || d[2] != d[0]
+      || e[0] != u'\x1234' || e[0] != u'\x{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || e[1] != u'\xBFFD' || e[1] != u'\x{00bFfD}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || e[2] != e[0]
+      || f[0] != u'\x29c' || f[0] != u'\o{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || f[1] != u'\xbFFD' || f[1] != u'\o{137775}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || f[2] != f[1])
+    __builtin_abort ();
+  if (g[0] != L'\u1234' || g[0] != L'\u{1234}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || g[1] != L'\U0000BFFD' || g[1] != L'\u{00000bFfD}'			/* { dg-error "delimited escape sequences are only valid in" } */
+      || g[2] != g[0]
+      || h[0] != L'\x1234' || h[0] != L'\x{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || h[1] != L'\xBFFD' || h[1] != L'\x{00bFfD}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || h[2] != h[0]
+      || i[0] != L'\x29c' || i[0] != L'\o{001234}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || i[1] != L'\xbFFD' || i[1] != L'\o{137775}'				/* { dg-error "delimited escape sequences are only valid in" } */
+      || i[2] != i[1])
+    __builtin_abort ();
+  if (k[0] != '\x034' || k[0] != '\x{0034}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || k[1] != '\x3D' || k[1] != '\x{3d}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || l[0] != '\x1c' || l[0] != '\o{0034}'					/* { dg-error "delimited escape sequences are only valid in" } */
+      || l[1] != '\x07e' || l[1] != '\o{176}' || l[1] != '\176')		/* { dg-error "delimited escape sequences are only valid in" } */
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-1.c b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-1.c
new file mode 100644
index 0000000..59468af
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-1.c
@@ -0,0 +1,6 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do run } */
+/* { dg-require-effective-target wchar } */
+/* { dg-options "-std=c2y -pedantic-errors -Wno-c++-compat" } */
+
+#include "../../c-c++-common/cpp/delimited-escape-seq-1.c"
diff --git a/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-2.c b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-2.c
new file mode 100644
index 0000000..7cc841c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-2.c
@@ -0,0 +1,5 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -pedantic-errors -Wno-c++-compat" } */
+
+#include "../../c-c++-common/cpp/delimited-escape-seq-2.c"
diff --git a/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-3.c b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-3.c
new file mode 100644
index 0000000..211dc84
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-3.c
@@ -0,0 +1,30 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do compile } */
+/* { dg-require-effective-target wchar } */
+/* { dg-options "-std=c2y -pedantic-errors -Wno-c++-compat" } */
+
+typedef __CHAR32_TYPE__ char32_t;
+
+const char32_t *a = U"\u{}";				/* { dg-error "empty delimited escape sequence" } */
+							/* { dg-error "is not a valid universal character" "" { target c } .-1 } */
+const char32_t *b = U"\u{12" "34}";			/* { dg-error "'\\\\u\\{' not terminated with '\\}' after" } */
+const char32_t *c = U"\u{0000ffffffff}";		/* { dg-error "is not a valid universal character" } */
+const char32_t *d = U"\u{010000edcb}";			/* { dg-error "is not a valid universal character" } */
+const char32_t *e = U"\u{02000000000000000000edcb}";	/* { dg-error "is not a valid universal character" } */
+const char32_t *f = U"\u{123ghij}";			/* { dg-error "'\\\\u\\{' not terminated with '\\}' after" } */
+const char32_t *g = U"\u{123.}";			/* { dg-error "'\\\\u\\{' not terminated with '\\}' after" } */
+const char32_t *h = U"\u{.}";				/* { dg-error "'\\\\u\\{' not terminated with '\\}' after" } */
+const char32_t *i = U"\x{}";				/* { dg-error "empty delimited escape sequence" } */
+const char32_t *j = U"\x{12" "34}";			/* { dg-error "'\\\\x\\{' not terminated with '\\}' after" } */
+const char32_t *k = U"\x{0000ffffffff}";
+const char32_t *l = U"\x{010000edcb}";			/* { dg-error "hex escape sequence out of range" } */
+const char32_t *m = U"\x{02000000000000000000edcb}";	/* { dg-error "hex escape sequence out of range" } */
+const char32_t *n = U"\x{123ghij}";			/* { dg-error "'\\\\x\\{' not terminated with '\\}' after" } */
+const char32_t *o = U"\x{123.}";			/* { dg-error "'\\\\x\\{' not terminated with '\\}' after" } */
+const char32_t *p = U"\o{}";				/* { dg-error "empty delimited escape sequence" } */
+const char32_t *q = U"\o{12" "34}";			/* { dg-error "'\\\\o\\{' not terminated with '\\}' after" } */
+const char32_t *r = U"\o{0000037777777777}";
+const char32_t *s = U"\o{040000166713}";		/* { dg-error "octal escape sequence out of range" } */
+const char32_t *t = U"\o{02000000000000000000000166713}";/* { dg-error "octal escape sequence out of range" } */
+const char32_t *u = U"\o{1238}";			/* { dg-error "'\\\\o\\{' not terminated with '\\}' after" } */
+const char32_t *v = U"\o{.}";				/* { dg-error "'\\\\o\\{' not terminated with '\\}' after" } */
diff --git a/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-4.c b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-4.c
new file mode 100644
index 0000000..bdb0e47
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/c2y-delimited-escape-seq-4.c
@@ -0,0 +1,87 @@
+/* N3353 - Delimited escape sequences */
+/* { dg-do compile } */
+/* { dg-require-effective-target wchar } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat -Wno-c++-compat" } */
+
+#include <wchar.h>
+typedef __CHAR16_TYPE__ char16_t;
+typedef __CHAR32_TYPE__ char32_t;
+
+const char32_t *a = U"\u{1234}\u{10fffd}\u{000000000000000000000000000000000000000000000000000000000001234}\u{10FFFD}";		/* { dg-warning "delimited escape sequences are only valid in" } */
+const char32_t *b = U"\x{1234}\x{10fffd}\x{000000000000000000000000000000000000000000000000000000000001234}";			/* { dg-warning "delimited escape sequences are only valid in" } */
+const char32_t *c = U"\o{1234}\o{4177775}\o{000000000000000000000000000000000000000000000000000000000000000000000000004177775}";/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *d = u"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *e = u"\x{1234}\x{BffD}\x{000001234}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const char16_t *f = u"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *g = L"\u{1234}\u{bFFd}\u{00000000000000000000000000000001234}";							/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *h = L"\x{1234}\x{bFFd}\x{000001234}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const wchar_t *i = L"\o{1234}\o{137775}\o{000000000000000137775}";								/* { dg-warning "delimited escape sequences are only valid in" } */
+const char *k = "\x{34}\x{000000000000000003D}";										/* { dg-warning "delimited escape sequences are only valid in" } */
+const char *l = "\o{34}\o{000000000000000176}";											/* { dg-warning "delimited escape sequences are only valid in" } */
+
+#if U'\u{1234}' != U'\u1234' || U'\u{10fffd}' != U'\U0010FFFD' \
+    || U'\x{00000001234}' != U'\x1234' || U'\x{010fffd}' != U'\x10FFFD' \
+    || U'\o{1234}' != U'\x29c' || U'\o{004177775}' != U'\x10FFFD' \
+    || u'\u{1234}' != u'\u1234' || u'\u{0bffd}' != u'\uBFFD' \
+    || u'\x{00000001234}' != u'\x1234' || u'\x{0Bffd}' != u'\x0bFFD' \
+    || u'\o{1234}' != u'\x29c' || u'\o{00137775}' != u'\xBFFD' \
+    || L'\u{1234}' != L'\u1234' || L'\u{0bffd}' != L'\uBFFD' \
+    || L'\x{00000001234}' != L'\x1234' || L'\x{0bffd}' != L'\x0bFFD' \
+    || L'\o{1234}' != L'\x29c' || L'\o{00137775}' != L'\xBFFD' \
+    || '\x{34}' != '\x034' || '\x{0003d}' != '\x003D' \
+    || '\o{34}' != '\x1C' || '\o{176}' != '\x007E'
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+/* { dg-warning "delimited escape sequences are only valid in" "" { target *-*-* } .-11 } */
+#error Bad
+#endif
+
+int
+main ()
+{
+  if (a[0] != U'\u1234' || a[0] != U'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || a[1] != U'\U0010FFFD' || a[1] != U'\u{000010fFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || a[2] != a[0]
+      || a[3] != a[1]
+      || b[0] != U'\x1234' || b[0] != U'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || b[1] != U'\x10FFFD' || b[1] != U'\x{0010fFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || b[2] != b[0]
+      || c[0] != U'\x29c' || c[0] != U'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || c[1] != U'\x10FFFD' || c[1] != U'\o{4177775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || c[2] != c[1])
+    __builtin_abort ();
+  if (d[0] != u'\u1234' || d[0] != u'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || d[1] != u'\U0000BFFD' || d[1] != u'\u{00000bFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || d[2] != d[0]
+      || e[0] != u'\x1234' || e[0] != u'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || e[1] != u'\xBFFD' || e[1] != u'\x{00bFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || e[2] != e[0]
+      || f[0] != u'\x29c' || f[0] != u'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || f[1] != u'\xbFFD' || f[1] != u'\o{137775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || f[2] != f[1])
+    __builtin_abort ();
+  if (g[0] != L'\u1234' || g[0] != L'\u{1234}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || g[1] != L'\U0000BFFD' || g[1] != L'\u{00000bFfD}'			/* { dg-warning "delimited escape sequences are only valid in" } */
+      || g[2] != g[0]
+      || h[0] != L'\x1234' || h[0] != L'\x{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || h[1] != L'\xBFFD' || h[1] != L'\x{00bFfD}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || h[2] != h[0]
+      || i[0] != L'\x29c' || i[0] != L'\o{001234}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || i[1] != L'\xbFFD' || i[1] != L'\o{137775}'				/* { dg-warning "delimited escape sequences are only valid in" } */
+      || i[2] != i[1])
+    __builtin_abort ();
+  if (k[0] != '\x034' || k[0] != '\x{0034}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || k[1] != '\x3D' || k[1] != '\x{3d}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || l[0] != '\x1c' || l[0] != '\o{0034}'					/* { dg-warning "delimited escape sequences are only valid in" } */
+      || l[1] != '\x07e' || l[1] != '\o{176}' || l[1] != '\176')		/* { dg-warning "delimited escape sequences are only valid in" } */
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/octal-constants-1.c b/gcc/testsuite/gcc.dg/octal-constants-1.c
new file mode 100644
index 0000000..5e22853
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/octal-constants-1.c
@@ -0,0 +1,311 @@
+/* Test for octal integer constants.  */
+
+/* Derived from: binary-constants-1.c, by Jakub Jelinek <jakub@redhat.com>.  */
+/* Origin: Joerg Wunsch <j.gnu@uriah.heep.sax.de>.  */
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99" } */
+
+#include <limits.h>
+
+/* Assertion that constant C is of type T.  */
+#define ASSERT_CONST_TYPE(C, T)			\
+	do {					\
+	  typedef T type;			\
+	  typedef type **typepp;		\
+	  typedef __typeof__((C)) ctype;	\
+	  typedef ctype **ctypepp;		\
+	  typepp x = 0;				\
+	  ctypepp y = 0;			\
+	  x = y;				\
+	  y = x;				\
+	} while (0)
+
+/* (T *) if E is zero, (void *) otherwise.  */
+#define type_if_not(T, E) __typeof__(0 ? (T *)0 : (void *)(E))
+
+/* (T *) if E is nonzero, (void *) otherwise.  */
+#define type_if(T, E) type_if_not(T, !(E))
+
+/* Combine pointer types, all but one (void *).  */
+#define type_comb2(T1, T2) __typeof__(0 ? (T1)0 : (T2)0)
+#define type_comb3(T1, T2, T3) type_comb2(T1, type_comb2(T2, T3))
+#define type_comb4(T1, T2, T3, T4)				\
+	type_comb2(T1, type_comb2(T2, type_comb2(T3, T4)))
+#define type_comb6(T1, T2, T3, T4, T5, T6)				   \
+	type_comb2(T1,							   \
+		   type_comb2(T2,					   \
+			      type_comb2(T3,				   \
+					 type_comb2(T4,			   \
+						    type_comb2(T5, T6)))))
+
+/* (T1 *) if E1, otherwise (T2 *) if E2.  */
+#define first_of2p(T1, E1, T2, E2) type_comb2(type_if(T1, (E1)),	   \
+					     type_if(T2, (!(E1) && (E2))))
+/* (T1 *) if E1, otherwise (T2 *) if E2, otherwise (T3 *) if E3.  */
+#define first_of3p(T1, E1, T2, E2, T3, E3)			\
+	type_comb3(type_if(T1, (E1)),				\
+		   type_if(T2, (!(E1) && (E2))),		\
+		   type_if(T3, (!(E1) && !(E2) && (E3))))
+/* (T1 *) if E1, otherwise (T2 *) if E2, otherwise (T3 *) if E3, otherwise
+   (T4 *) if E4.  */
+#define first_of4p(T1, E1, T2, E2, T3, E3, T4, E4)			\
+	type_comb4(type_if(T1, (E1)),					\
+		   type_if(T2, (!(E1) && (E2))),			\
+		   type_if(T3, (!(E1) && !(E2) && (E3))),		\
+		   type_if(T4, (!(E1) && !(E2) && !(E3) && (E4))))
+/* (T1 *) if E1, otherwise (T2 *) if E2, otherwise (T3 *) if E3, otherwise
+   (T4 *) if E4, otherwise (T5 *) if E5, otherwise (T6 *) if E6.  */
+#define first_of6p(T1, E1, T2, E2, T3, E3, T4, E4, T5, E5, T6, E6)	    \
+	type_comb6(type_if(T1, (E1)),					    \
+		   type_if(T2, (!(E1) && (E2))),			    \
+		   type_if(T3, (!(E1) && !(E2) && (E3))),		    \
+		   type_if(T4, (!(E1) && !(E2) && !(E3) && (E4))),	    \
+		   type_if(T5, (!(E1) && !(E2) && !(E3) && !(E4) && (E5))), \
+		   type_if(T6, (!(E1) && !(E2) && !(E3)			    \
+				&& !(E4) && !(E5) && (E6))))
+
+/* Likewise, but return the original type rather than a pointer type.  */
+#define first_of2(T1, E1, T2, E2)			\
+	__typeof__(*((first_of2p(T1, (E1), T2, (E2)))0))
+#define first_of3(T1, E1, T2, E2, T3, E3)				\
+	__typeof__(*((first_of3p(T1, (E1), T2, (E2), T3, (E3)))0))
+#define first_of4(T1, E1, T2, E2, T3, E3, T4, E4)			    \
+	__typeof__(*((first_of4p(T1, (E1), T2, (E2), T3, (E3), T4, (E4)))0))
+#define first_of6(T1, E1, T2, E2, T3, E3, T4, E4, T5, E5, T6, E6)	\
+	__typeof__(*((first_of6p(T1, (E1), T2, (E2), T3, (E3),		\
+				 T4, (E4), T5, (E5), T6, (E6)))0))
+
+/* Types of constants according to the C99 rules.  */
+#define C99_UNSUF_TYPE(C)					\
+	first_of6(int, (C) <= INT_MAX,				\
+		  unsigned int, (C) <= UINT_MAX,		\
+		  long int, (C) <= LONG_MAX,			\
+		  unsigned long int, (C) <= ULONG_MAX,		\
+		  long long int, (C) <= LLONG_MAX,		\
+		  unsigned long long int, (C) <= ULLONG_MAX)
+#define C99_SUFu_TYPE(C)					\
+	first_of3(unsigned int, (C) <= UINT_MAX,		\
+		  unsigned long int, (C) <= ULONG_MAX,		\
+		  unsigned long long int, (C) <= ULLONG_MAX)
+#define C99_SUFl_TYPE(C)					\
+	first_of4(long int, (C) <= LONG_MAX,			\
+		  unsigned long int, (C) <= ULONG_MAX,		\
+		  long long int, (C) <= LLONG_MAX,		\
+		  unsigned long long int, (C) <= ULLONG_MAX)
+#define C99_SUFul_TYPE(C)					\
+	first_of2(unsigned long int, (C) <= ULONG_MAX,		\
+		  unsigned long long int, (C) <= ULLONG_MAX)
+#define C99_SUFll_TYPE(C)					\
+	first_of2(long long int, (C) <= LLONG_MAX,		\
+		  unsigned long long int, (C) <= ULLONG_MAX)
+
+/* Checks that constants have correct type.  */
+#define CHECK_UNSUF_TYPE(C)				\
+	ASSERT_CONST_TYPE((C), C99_UNSUF_TYPE((C)))
+#define CHECK_SUFu_TYPE(C) ASSERT_CONST_TYPE((C), C99_SUFu_TYPE((C)))
+#define CHECK_SUFl_TYPE(C)				\
+	ASSERT_CONST_TYPE((C), C99_SUFl_TYPE((C)))
+#define CHECK_SUFul_TYPE(C) ASSERT_CONST_TYPE((C), C99_SUFul_TYPE((C)))
+#define CHECK_SUFll_TYPE(C)				\
+	ASSERT_CONST_TYPE((C), C99_SUFll_TYPE((C)))
+#define CHECK_SUFull_TYPE(C) ASSERT_CONST_TYPE((C), unsigned long long int)
+
+/* Check an octal or hexadecimal value, with all suffixes.  */
+#define CHECK_CONST(C)                  	\
+	CHECK_UNSUF_TYPE(C);                    \
+	CHECK_SUFu_TYPE(C##u);			\
+	CHECK_SUFu_TYPE(C##U);			\
+	CHECK_SUFl_TYPE(C##l);                  \
+	CHECK_SUFl_TYPE(C##L);                  \
+	CHECK_SUFul_TYPE(C##ul);		\
+	CHECK_SUFul_TYPE(C##uL);		\
+	CHECK_SUFul_TYPE(C##Ul);		\
+	CHECK_SUFul_TYPE(C##UL);		\
+	CHECK_SUFll_TYPE(C##ll);		\
+	CHECK_SUFll_TYPE(C##LL);		\
+	CHECK_SUFull_TYPE(C##ull);		\
+	CHECK_SUFull_TYPE(C##uLL);		\
+	CHECK_SUFull_TYPE(C##Ull);		\
+	CHECK_SUFull_TYPE(C##ULL);
+
+#define CHECK_OCT_CONST(C)			\
+	CHECK_CONST(0o##C);                     \
+	CHECK_CONST(0O##C);
+
+/* True iff "long long" is at least B bits.  This presumes that (B-2)/3 is at
+   most 63.  */
+#define LLONG_AT_LEAST(B)			\
+	(LLONG_MAX >> ((B)-2)/3 >> ((B)-2)/3	\
+	 >> ((B)-2 - ((B)-2)/3 - ((B)-2)/3))
+
+#define LLONG_HAS_BITS(B) (LLONG_AT_LEAST((B)) && !LLONG_AT_LEAST((B) + 1))
+
+#define FOO 0o1307
+#if !FOO
+# error "preprocessor does not accept octal constants"
+#endif
+
+void
+foo (void)
+{
+  /* Check all 2^n and 2^n - 1 up to 2^72 - 1.  */
+  CHECK_OCT_CONST(1);
+  CHECK_OCT_CONST(2);
+  CHECK_OCT_CONST(3);
+  CHECK_OCT_CONST(4);
+  CHECK_OCT_CONST(7);
+  CHECK_OCT_CONST(10);
+  CHECK_OCT_CONST(17);
+  CHECK_OCT_CONST(20);
+  CHECK_OCT_CONST(37);
+  CHECK_OCT_CONST(40);
+  CHECK_OCT_CONST(77);
+  CHECK_OCT_CONST(100);
+  CHECK_OCT_CONST(177);
+  CHECK_OCT_CONST(200);
+  CHECK_OCT_CONST(377);
+  CHECK_OCT_CONST(400);
+  CHECK_OCT_CONST(777);
+  CHECK_OCT_CONST(1000);
+  CHECK_OCT_CONST(1777);
+  CHECK_OCT_CONST(2000);
+  CHECK_OCT_CONST(3777);
+  CHECK_OCT_CONST(4000);
+  CHECK_OCT_CONST(7777);
+  CHECK_OCT_CONST(10000);
+  CHECK_OCT_CONST(17777);
+  CHECK_OCT_CONST(20000);
+  CHECK_OCT_CONST(37777);
+  CHECK_OCT_CONST(40000);
+  CHECK_OCT_CONST(77777);
+  CHECK_OCT_CONST(100000);
+  CHECK_OCT_CONST(177777);
+  CHECK_OCT_CONST(200000);
+  CHECK_OCT_CONST(377777);
+  CHECK_OCT_CONST(400000);
+  CHECK_OCT_CONST(777777);
+  CHECK_OCT_CONST(1000000);
+  CHECK_OCT_CONST(1777777);
+  CHECK_OCT_CONST(2000000);
+  CHECK_OCT_CONST(3777777);
+  CHECK_OCT_CONST(4000000);
+  CHECK_OCT_CONST(7777777);
+  CHECK_OCT_CONST(10000000);
+  CHECK_OCT_CONST(17777777);
+  CHECK_OCT_CONST(20000000);
+  CHECK_OCT_CONST(37777777);
+  CHECK_OCT_CONST(40000000);
+  CHECK_OCT_CONST(77777777);
+  CHECK_OCT_CONST(100000000);
+  CHECK_OCT_CONST(177777777);
+  CHECK_OCT_CONST(200000000);
+  CHECK_OCT_CONST(377777777);
+  CHECK_OCT_CONST(400000000);
+  CHECK_OCT_CONST(777777777);
+  CHECK_OCT_CONST(1000000000);
+  CHECK_OCT_CONST(1777777777);
+  CHECK_OCT_CONST(2000000000);
+  CHECK_OCT_CONST(3777777777);
+  CHECK_OCT_CONST(4000000000);
+  CHECK_OCT_CONST(7777777777);
+  CHECK_OCT_CONST(10000000000);
+  CHECK_OCT_CONST(17777777777);
+  CHECK_OCT_CONST(20000000000);
+  CHECK_OCT_CONST(37777777777);
+  CHECK_OCT_CONST(40000000000);
+  CHECK_OCT_CONST(77777777777);
+  CHECK_OCT_CONST(100000000000);
+  CHECK_OCT_CONST(177777777777);
+  CHECK_OCT_CONST(200000000000);
+  CHECK_OCT_CONST(377777777777);
+  CHECK_OCT_CONST(400000000000);
+  CHECK_OCT_CONST(777777777777);
+  CHECK_OCT_CONST(1000000000000);
+  CHECK_OCT_CONST(1777777777777);
+  CHECK_OCT_CONST(2000000000000);
+  CHECK_OCT_CONST(3777777777777);
+  CHECK_OCT_CONST(4000000000000);
+  CHECK_OCT_CONST(7777777777777);
+  CHECK_OCT_CONST(10000000000000);
+  CHECK_OCT_CONST(17777777777777);
+  CHECK_OCT_CONST(20000000000000);
+  CHECK_OCT_CONST(37777777777777);
+  CHECK_OCT_CONST(40000000000000);
+  CHECK_OCT_CONST(77777777777777);
+  CHECK_OCT_CONST(100000000000000);
+  CHECK_OCT_CONST(177777777777777);
+  CHECK_OCT_CONST(200000000000000);
+  CHECK_OCT_CONST(377777777777777);
+  CHECK_OCT_CONST(400000000000000);
+  CHECK_OCT_CONST(777777777777777);
+  CHECK_OCT_CONST(1000000000000000);
+  CHECK_OCT_CONST(1777777777777777);
+  CHECK_OCT_CONST(2000000000000000);
+  CHECK_OCT_CONST(3777777777777777);
+  CHECK_OCT_CONST(4000000000000000);
+  CHECK_OCT_CONST(7777777777777777);
+  CHECK_OCT_CONST(10000000000000000);
+  CHECK_OCT_CONST(17777777777777777);
+  CHECK_OCT_CONST(20000000000000000);
+  CHECK_OCT_CONST(37777777777777777);
+  CHECK_OCT_CONST(40000000000000000);
+  CHECK_OCT_CONST(77777777777777777);
+  CHECK_OCT_CONST(100000000000000000);
+  CHECK_OCT_CONST(177777777777777777);
+  CHECK_OCT_CONST(200000000000000000);
+  CHECK_OCT_CONST(377777777777777777);
+  CHECK_OCT_CONST(400000000000000000);
+  CHECK_OCT_CONST(777777777777777777);
+  CHECK_OCT_CONST(1000000000000000000);
+  CHECK_OCT_CONST(1777777777777777777);
+  CHECK_OCT_CONST(2000000000000000000);
+  CHECK_OCT_CONST(3777777777777777777);
+  CHECK_OCT_CONST(4000000000000000000);
+  CHECK_OCT_CONST(7777777777777777777);
+  CHECK_OCT_CONST(10000000000000000000);
+  CHECK_OCT_CONST(17777777777777777777);
+  CHECK_OCT_CONST(20000000000000000000);
+  CHECK_OCT_CONST(37777777777777777777);
+  CHECK_OCT_CONST(40000000000000000000);
+  CHECK_OCT_CONST(77777777777777777777);
+  CHECK_OCT_CONST(100000000000000000000);
+  CHECK_OCT_CONST(177777777777777777777);
+  CHECK_OCT_CONST(200000000000000000000);
+  CHECK_OCT_CONST(377777777777777777777);
+  CHECK_OCT_CONST(400000000000000000000);
+  CHECK_OCT_CONST(777777777777777777777);
+  CHECK_OCT_CONST(1000000000000000000000);
+  CHECK_OCT_CONST(1777777777777777777777);
+#if LLONG_AT_LEAST(65)
+  CHECK_OCT_CONST(2000000000000000000000);
+  CHECK_OCT_CONST(3777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(66)
+  CHECK_OCT_CONST(4000000000000000000000);
+  CHECK_OCT_CONST(7777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(67)
+  CHECK_OCT_CONST(10000000000000000000000);
+  CHECK_OCT_CONST(17777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(68)
+  CHECK_OCT_CONST(20000000000000000000000);
+  CHECK_OCT_CONST(37777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(69)
+  CHECK_OCT_CONST(40000000000000000000000);
+  CHECK_OCT_CONST(77777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(70)
+  CHECK_OCT_CONST(100000000000000000000000);
+  CHECK_OCT_CONST(177777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(71)
+  CHECK_OCT_CONST(200000000000000000000000);
+  CHECK_OCT_CONST(377777777777777777777777);
+#endif
+#if LLONG_AT_LEAST(72)
+  CHECK_OCT_CONST(400000000000000000000000);
+  CHECK_OCT_CONST(777777777777777777777777);
+#endif
+}
diff --git a/gcc/testsuite/gcc.dg/octal-constants-2.c b/gcc/testsuite/gcc.dg/octal-constants-2.c
new file mode 100644
index 0000000..85c9529
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/octal-constants-2.c
@@ -0,0 +1,16 @@
+/* Test for octal integer constants: -pedantic warnings.  */
+
+/* Origin: Joerg Wunsch <j.gnu@uriah.heep.sax.de>.  */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic -ftrack-macro-expansion=0" } */
+
+#define FOO 0o1307
+
+int
+foo (void)
+{
+#if FOO /* { dg-warning "'0o' prefixed constants are a C2Y feature or GCC extension" } */
+  return 23;
+#endif
+  return 0o1307; /* { dg-warning "'0o' prefixed constants are a C2Y feature or GCC extension" } */
+}
diff --git a/gcc/testsuite/gcc.dg/octal-constants-3.c b/gcc/testsuite/gcc.dg/octal-constants-3.c
new file mode 100644
index 0000000..0697172
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/octal-constants-3.c
@@ -0,0 +1,16 @@
+/* Test for octal integer constants: -pedantic-errors.  */
+
+/* Origin: Joerg Wunsch <j.gnu@uriah.heep.sax.de>.  */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors -ftrack-macro-expansion=0" } */
+
+#define FOO 0o1307
+
+int
+foo (void)
+{
+#if FOO /* { dg-error "'0o' prefixed constants are a C2Y feature or GCC extension" } */
+  return 23;
+#endif
+  return 0o1307; /* { dg-error "'0o' prefixed constants are a C2Y feature or GCC extension" } */
+}
diff --git a/gcc/testsuite/gcc.dg/octal-constants-4.c b/gcc/testsuite/gcc.dg/octal-constants-4.c
new file mode 100644
index 0000000..d2141de
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/octal-constants-4.c
@@ -0,0 +1,18 @@
+/* Test for octal integer constants: random errors.  */
+
+/* Origin: Joerg Wunsch <j.gnu@uriah.heep.sax.de>.  */
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99" } */
+
+void
+foo(void)
+{
+  double d;
+  int i;
+
+  d = 0o1307;
+  d = 0o1307p1; /* { dg-error "invalid suffix 'p1' on integer constant" } */
+  d = 0x1307p1;
+  i = 0oa011;   /* { dg-error "invalid suffix 'oa011' on integer constant" } */
+  i = 0o118;    /* { dg-error "invalid digit '8' in octal constant" } */
+}
diff --git a/gcc/testsuite/gcc.dg/system-octal-constants-1.c b/gcc/testsuite/gcc.dg/system-octal-constants-1.c
new file mode 100644
index 0000000..a6b8160
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/system-octal-constants-1.c
@@ -0,0 +1,18 @@
+/* 
+   Origin: Dodji Seketeli <dodji@redhat.com>
+   { dg-options "-std=iso9899:1999 -pedantic" } 
+   { dg-do compile } 
+ */
+
+#include "system-octal-constants-1.h"
+
+int
+foo (void)
+{
+#if OCTAL_INT_CONSTANT_IN_SYSTEM_HEADER /* A octal constant defined
+					   in system header.  No
+					   warning.  */
+  return 23;
+#endif
+  return 0o1307; /* { dg-warning "'0o' prefixed constants are a C2Y feature or GCC extension" } */
+}
diff --git a/gcc/testsuite/gcc.dg/system-octal-constants-1.h b/gcc/testsuite/gcc.dg/system-octal-constants-1.h
new file mode 100644
index 0000000..ec9dbe3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/system-octal-constants-1.h
@@ -0,0 +1,3 @@
+#pragma GCC system_header
+
+#define OCTAL_INT_CONSTANT_IN_SYSTEM_HEADER 0o1307