diff mbox series

c: Implement C2Y N3298 - Introduce complex literals [PR117029]

Message ID ZzICJdMXn9avC17f@tucnak
State New
Headers show
Series c: Implement C2Y N3298 - Introduce complex literals [PR117029] | expand

Commit Message

Jakub Jelinek Nov. 11, 2024, 1:09 p.m. UTC 
Hi!

The following patch implements the C2Y N3298 paper Introduce complex literals
by providing different (or no) diagnostics on imaginary constants (except
for integer ones).
For _DecimalN constants we don't support _Complex _DecimalN and error on any
i/j suffixes mixed with DD/DL/DF, so nothing changed there.

Smoke tested on x86_64-linux so far, ok for trunk if this passes
bootstrap/regtest?

2024-11-11  Jakub Jelinek  <jakub@redhat.com>

	PR c/117029
libcpp/
	* include/cpplib.h (struct cpp_options): Add imaginary_constants
	member.
	* init.cc (struct lang_flags): Add imaginary_constants bitfield.
	(lang_defaults): Add column for imaginary_constants.
	(cpp_set_lang): Copy over imaginary_constants.
	* expr.cc (cpp_classify_number): Diagnose CPP_N_IMAGINARY
	non-CPP_N_FLOATING constants differently for C.
gcc/testsuite/
	* gcc.dg/c23-imaginary-constants-1.c: New test.
	* gcc.dg/c23-imaginary-constants-2.c: New test.
	* gcc.dg/c23-imaginary-constants-3.c: New test.
	* gcc.dg/c23-imaginary-constants-4.c: New test.
	* gcc.dg/c23-imaginary-constants-5.c: New test.
	* gcc.dg/c23-imaginary-constants-6.c: New test.
	* gcc.dg/c23-imaginary-constants-7.c: New test.
	* gcc.dg/c23-imaginary-constants-8.c: New test.
	* gcc.dg/c23-imaginary-constants-9.c: New test.
	* gcc.dg/c23-imaginary-constants-10.c: New test.
	* gcc.dg/c2y-imaginary-constants-1.c: New test.
	* gcc.dg/c2y-imaginary-constants-2.c: New test.
	* gcc.dg/c2y-imaginary-constants-3.c: New test.
	* gcc.dg/c2y-imaginary-constants-4.c: New test.
	* gcc.dg/c2y-imaginary-constants-5.c: New test.
	* gcc.dg/c2y-imaginary-constants-6.c: New test.
	* gcc.dg/c2y-imaginary-constants-7.c: New test.
	* gcc.dg/c2y-imaginary-constants-8.c: New test.
	* gcc.dg/c2y-imaginary-constants-9.c: New test.
	* gcc.dg/c2y-imaginary-constants-10.c: New test.
	* gcc.dg/c2y-imaginary-constants-11.c: New test.
	* gcc.dg/c2y-imaginary-constants-12.c: New test.


	Jakub

Comments

Joseph Myers Nov. 12, 2024, 12:55 a.m. UTC | #1 
On Mon, 11 Nov 2024, Jakub Jelinek wrote:

> Hi!
> 
> The following patch implements the C2Y N3298 paper Introduce complex literals
> by providing different (or no) diagnostics on imaginary constants (except
> for integer ones).
> For _DecimalN constants we don't support _Complex _DecimalN and error on any
> i/j suffixes mixed with DD/DL/DF, so nothing changed there.
> 
> Smoke tested on x86_64-linux so far, ok for trunk if this passes
> bootstrap/regtest?

OK.
diff mbox series

Patch

--- libcpp/include/cpplib.h.jj	2024-11-01 19:39:10.886073209 +0100
+++ libcpp/include/cpplib.h	2024-11-11 11:25:51.120535730 +0100
@@ -524,6 +524,9 @@  struct cpp_options
   /* Nonzero for C++ 2014 Standard binary constants.  */
   unsigned char binary_constants;
 
+  /* Nonzero for C2Y imaginary (floating) constants.  */
+  unsigned char imaginary_constants;
+
   /* Nonzero for C++ 2014 Standard digit separators.  */
   unsigned char digit_separators;
 
--- libcpp/init.cc.jj	2024-10-25 10:03:16.785374003 +0200
+++ libcpp/init.cc	2024-11-11 11:29:07.757773751 +0100
@@ -112,44 +112,45 @@  struct lang_flags
   unsigned int octal_constants : 1;
   unsigned int true_false : 1;
   unsigned int embed : 1;
+  unsigned int imaginary_constants : 1;
 };
 
 static const struct lang_flags lang_defaults[] = {
   /*					       u         e w   n
 					 b d   8         l a   a   t
 			     x         u i i   c v s   s i r d m o r e
-		       x     i   d u r d n g t h a c   z f n e e c u m
-		   c c n x c d s i l l l c s r l o o d l d d l d t f b
-		   9 + u i 1 i t g i i i s e i i p p f i e i i u a a e
-		   9 + m d 1 d d r t t t t p g t t e p t f r m c l l d  */
-  /* GNUC89   */ { 0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
-  /* GNUC99   */ { 1,0,1,1,0,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
-  /* GNUC11   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
-  /* GNUC17   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
-  /* GNUC23   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1 },
-  /* GNUC2Y   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1 },
-  /* STDC89   */ { 0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC94   */ { 0,0,0,0,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC99   */ { 1,0,1,1,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC11   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC17   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC23   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1 },
-  /* STDC2Y   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1 },
-  /* GNUCXX   */ { 0,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0 },
-  /* CXX98    */ { 0,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0 },
-  /* GNUCXX11 */ { 1,1,1,1,1,1,0,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0 },
-  /* CXX11    */ { 1,1,0,1,1,1,1,1,1,1,1,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0 },
-  /* GNUCXX14 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,0,1,1,0,0,0,0,0,0,0,1,0 },
-  /* CXX14    */ { 1,1,0,1,1,1,1,1,1,1,1,1,1,1,0,0,1,0,0,0,0,0,0,0,1,0 },
-  /* GNUCXX17 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
-  /* CXX17    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,0 },
-  /* GNUCXX20 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
-  /* CXX20    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
-  /* GNUCXX23 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
-  /* CXX23    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
-  /* GNUCXX26 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
-  /* CXX26    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
-  /* ASM      */ { 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
+		       x     i   d u r d n g t h a c   z f n e e c u m i
+		   c c n x c d s i l l l c s r l o o d l d d l d t f b m
+		   9 + u i 1 i t g i i i s e i i p p f i e i i u a a e a
+		   9 + m d 1 d d r t t t t p g t t e p t f r m c l l d g */
+  /* GNUC89   */ { 0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0 },
+  /* GNUC99   */ { 1,0,1,1,0,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0 },
+  /* GNUC11   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0 },
+  /* GNUC17   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0 },
+  /* GNUC23   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1,0 },
+  /* GNUC2Y   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1,1 },
+  /* STDC89   */ { 0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC94   */ { 0,0,0,0,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC99   */ { 1,0,1,1,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC11   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC17   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC23   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1,0 },
+  /* STDC2Y   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1,1 },
+  /* GNUCXX   */ { 0,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* CXX98    */ { 0,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0,0 },
+  /* GNUCXX11 */ { 1,1,1,1,1,1,0,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* CXX11    */ { 1,1,0,1,1,1,1,1,1,1,1,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0,0 },
+  /* GNUCXX14 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,0,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* CXX14    */ { 1,1,0,1,1,1,1,1,1,1,1,1,1,1,0,0,1,0,0,0,0,0,0,0,1,0,0 },
+  /* GNUCXX17 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* CXX17    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0 },
+  /* GNUCXX20 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* CXX20    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0,0 },
+  /* GNUCXX23 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0 },
+  /* CXX23    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0 },
+  /* GNUCXX26 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0 },
+  /* CXX26    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0 },
+  /* ASM      */ { 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
 };
 
 /* Sets internal flags correctly for a given language.  */
@@ -186,6 +187,7 @@  cpp_set_lang (cpp_reader *pfile, enum c_
   CPP_OPTION (pfile, octal_constants)		 = l->octal_constants;
   CPP_OPTION (pfile, true_false)		 = l->true_false;
   CPP_OPTION (pfile, embed)			 = l->embed;
+  CPP_OPTION (pfile, imaginary_constants)	 = l->imaginary_constants;
 }
 
 /* Initialize library global state.  */
--- libcpp/expr.cc.jj	2024-10-25 10:03:16.784374017 +0200
+++ libcpp/expr.cc	2024-11-11 11:40:01.991584352 +0100
@@ -911,8 +911,25 @@  cpp_classify_number (cpp_reader *pfile,
 
  syntax_ok:
   if (result & CPP_N_IMAGINARY)
-    cpp_pedwarning_with_line (pfile, CPP_W_PEDANTIC, virtual_location, 0,
-			      "imaginary constants are a GCC extension");
+    {
+      if (CPP_OPTION (pfile, cplusplus) || (result & CPP_N_FLOATING) == 0)
+	cpp_pedwarning_with_line (pfile, CPP_W_PEDANTIC, virtual_location, 0,
+				  "imaginary constants are a GCC extension");
+      else
+	{
+	  bool warned = false;
+	  if (!CPP_OPTION (pfile, imaginary_constants) && CPP_PEDANTIC (pfile))
+	    warned
+	      = cpp_pedwarning_with_line (pfile, CPP_W_PEDANTIC,
+					  virtual_location, 0,
+					  "imaginary constants are a C2Y "
+					  "feature or GCC extension");
+	  if (!warned && CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) > 0)
+	    cpp_warning_with_line (pfile, CPP_W_C23_C2Y_COMPAT,
+				   virtual_location, 0,
+				   "imaginary constants are a C2Y feature");
+	}
+    }
   if (radix == 2)
     {
       bool warned = false;
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-1.c.jj	2024-11-11 12:02:26.057705696 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-1.c	2024-11-11 12:40:31.285612990 +0100
@@ -0,0 +1,58 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c23 -pedantic" } */
+
+_Complex float a = 1.if;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float b = 2.Fj;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float c = 3.fI;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float d = 4.JF;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double e = 1.i;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double f = 2.j;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double g = 3.I;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double h = 4.J;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double i = 1.il;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double j = 2.Lj;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double k = 3.lI;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double l = 4.JL;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex float m = 1.if;
+__extension__ _Complex float n = 2.Fj;
+__extension__ _Complex float o = 3.fI;
+__extension__ _Complex float p = 4.JF;
+__extension__ _Complex double q = 1.i;
+__extension__ _Complex double r = 2.j;
+__extension__ _Complex double s = 3.I;
+__extension__ _Complex double t = 4.J;
+__extension__ _Complex long double u = 1.il;
+__extension__ _Complex long double v = 2.Lj;
+__extension__ _Complex long double w = 3.lI;
+__extension__ _Complex long double x = 4.JL;
+
+int
+main ()
+{
+  if (a * a != -1.f
+      || b * b != -4.f
+      || c * c != -9.f
+      || d * d != -16.f
+      || e * e != -1.
+      || f * f != -4.
+      || g * g != -9.
+      || h * h != -16.
+      || i * i != -1.L
+      || j * j != -4.L
+      || k * k != -9.L
+      || l * l != -16.L
+      || m * m != -1.f
+      || n * n != -4.f
+      || o * o != -9.f
+      || p * p != -16.f
+      || q * q != -1.
+      || r * r != -4.
+      || s * s != -9.
+      || t * t != -16.
+      || u * u != -1.L
+      || v * v != -4.L
+      || w * w != -9.L
+      || x * x != -16.L)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-2.c.jj	2024-11-11 12:07:57.347052616 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-2.c	2024-11-11 12:41:06.877113270 +0100
@@ -0,0 +1,28 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+
+_Complex float a = 1.if;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float b = 2.Fj;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float c = 3.fI;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex float d = 4.JF;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double e = 1.i;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double f = 2.j;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double g = 3.I;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex double h = 4.J;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double i = 1.il;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double j = 2.Lj;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double k = 3.lI;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex long double l = 4.JL;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex float m = 1.if;
+__extension__ _Complex float n = 2.Fj;
+__extension__ _Complex float o = 3.fI;
+__extension__ _Complex float p = 4.JF;
+__extension__ _Complex double q = 1.i;
+__extension__ _Complex double r = 2.j;
+__extension__ _Complex double s = 3.I;
+__extension__ _Complex double t = 4.J;
+__extension__ _Complex long double u = 1.il;
+__extension__ _Complex long double v = 2.Lj;
+__extension__ _Complex long double w = 3.lI;
+__extension__ _Complex long double x = 4.JL;
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-3.c.jj	2024-11-11 12:16:19.046006071 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-3.c	2024-11-11 12:41:52.496472761 +0100
@@ -0,0 +1,64 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c23 -pedantic" } */
+/* { dg-add-options float32 } */
+/* { dg-add-options float64 } */
+/* { dg-add-options float32x } */
+/* { dg-require-effective-target float32 } */
+/* { dg-require-effective-target float32x } */
+/* { dg-require-effective-target float64 } */
+
+_Complex _Float32 a = 1.if32;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 b = 2.F32j;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 c = 3.f32i;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 d = 4.JF32;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 e = 1.if64;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 f = 2.F64j;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 g = 3.f64i;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 h = 4.JF64;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x i = 1.if32x;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x j = 2.F32xj;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x k = 3.f32xI;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x l = 4.JF32x;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float32 m = 1.if32;
+__extension__ _Complex _Float32 n = 2.F32j;
+__extension__ _Complex _Float32 o = 3.f32i;
+__extension__ _Complex _Float32 p = 4.JF32;
+__extension__ _Complex _Float64 q = 1.if64;
+__extension__ _Complex _Float64 r = 2.F64j;
+__extension__ _Complex _Float64 s = 3.f64i;
+__extension__ _Complex _Float64 t = 4.JF64;
+__extension__ _Complex _Float32x u = 1.if32x;
+__extension__ _Complex _Float32x v = 2.F32xj;
+__extension__ _Complex _Float32x w = 3.f32xI;
+__extension__ _Complex _Float32x x = 4.JF32x;
+
+int
+main ()
+{
+  if (a * a != -1.f32
+      || b * b != -4.f32
+      || c * c != -9.f32
+      || d * d != -16.f32
+      || e * e != -1.f64
+      || f * f != -4.f64
+      || g * g != -9.f64
+      || h * h != -16.f64
+      || i * i != -1.f32x
+      || j * j != -4.f32x
+      || k * k != -9.f32x
+      || l * l != -16.f32x
+      || m * m != -1.f32
+      || n * n != -4.f32
+      || o * o != -9.f32
+      || p * p != -16.f32
+      || q * q != -1.f64
+      || r * r != -4.f64
+      || s * s != -9.f64
+      || t * t != -16.f64
+      || u * u != -1.f32x
+      || v * v != -4.f32x
+      || w * w != -9.f32x
+      || x * x != -16.f32x)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-4.c.jj	2024-11-11 12:23:18.943109280 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-4.c	2024-11-11 12:33:47.455282974 +0100
@@ -0,0 +1,34 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+/* { dg-add-options float32 } */
+/* { dg-add-options float64 } */
+/* { dg-add-options float32x } */
+/* { dg-require-effective-target float32 } */
+/* { dg-require-effective-target float32x } */
+/* { dg-require-effective-target float64 } */
+
+_Complex _Float32 a = 1.if32;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 b = 2.F32j;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 c = 3.f32i;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32 d = 4.JF32;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 e = 1.if64;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 f = 2.F64j;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 g = 3.f64i;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64 h = 4.JF64;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x i = 1.if32x;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x j = 2.F32xj;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x k = 3.f32xI;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float32x l = 4.JF32x;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float32 m = 1.if32;
+__extension__ _Complex _Float32 n = 2.F32j;
+__extension__ _Complex _Float32 o = 3.f32i;
+__extension__ _Complex _Float32 p = 4.JF32;
+__extension__ _Complex _Float64 q = 1.if64;
+__extension__ _Complex _Float64 r = 2.F64j;
+__extension__ _Complex _Float64 s = 3.f64i;
+__extension__ _Complex _Float64 t = 4.JF64;
+__extension__ _Complex _Float32x u = 1.if32x;
+__extension__ _Complex _Float32x v = 2.F32xj;
+__extension__ _Complex _Float32x w = 3.f32xI;
+__extension__ _Complex _Float32x x = 4.JF32x;
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-5.c.jj	2024-11-11 12:48:32.179861104 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-5.c	2024-11-11 12:49:24.990119636 +0100
@@ -0,0 +1,28 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c23 -pedantic" } */
+/* { dg-add-options float128 } */
+/* { dg-require-effective-target float128 } */
+
+_Complex _Float128 a = 1.if128;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 b = 2.F128j;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 c = 3.f128i;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 d = 4.JF128;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float128 e = 1.if128;
+__extension__ _Complex _Float128 f = 2.F128j;
+__extension__ _Complex _Float128 g = 3.f128i;
+__extension__ _Complex _Float128 h = 4.JF128;
+
+int
+main ()
+{
+  if (a * a != -1.f128
+      || b * b != -4.f128
+      || c * c != -9.f128
+      || d * d != -16.f128
+      || e * e != -1.f128
+      || f * f != -4.f128
+      || g * g != -9.f128
+      || h * h != -16.f128)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-6.c.jj	2024-11-11 12:49:48.686786924 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-6.c	2024-11-11 12:50:19.776350422 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+/* { dg-add-options float128 } */
+/* { dg-require-effective-target float128 } */
+
+_Complex _Float128 a = 1.if128;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 b = 2.F128j;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 c = 3.f128i;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float128 d = 4.JF128;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float128 e = 1.if128;
+__extension__ _Complex _Float128 f = 2.F128j;
+__extension__ _Complex _Float128 g = 3.f128i;
+__extension__ _Complex _Float128 h = 4.JF128;
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-7.c.jj	2024-11-11 12:50:47.402962537 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-7.c	2024-11-11 12:51:01.184769035 +0100
@@ -0,0 +1,28 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c23 -pedantic" } */
+/* { dg-add-options float16 } */
+/* { dg-require-effective-target float16 } */
+
+_Complex _Float16 a = 1.if16;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 b = 2.F16j;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 c = 3.f16i;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 d = 4.JF16;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float16 e = 1.if16;
+__extension__ _Complex _Float16 f = 2.F16j;
+__extension__ _Complex _Float16 g = 3.f16i;
+__extension__ _Complex _Float16 h = 4.JF16;
+
+int
+main ()
+{
+  if (a * a != -1.f16
+      || b * b != -4.f16
+      || c * c != -9.f16
+      || d * d != -16.f16
+      || e * e != -1.f16
+      || f * f != -4.f16
+      || g * g != -9.f16
+      || h * h != -16.f16)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-8.c.jj	2024-11-11 12:50:47.402962537 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-8.c	2024-11-11 12:51:09.646650228 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+/* { dg-add-options float16 } */
+/* { dg-require-effective-target float16 } */
+
+_Complex _Float16 a = 1.if16;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 b = 2.F16j;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 c = 3.f16i;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float16 d = 4.JF16;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float16 e = 1.if16;
+__extension__ _Complex _Float16 f = 2.F16j;
+__extension__ _Complex _Float16 g = 3.f16i;
+__extension__ _Complex _Float16 h = 4.JF16;
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-9.c.jj	2024-11-11 12:50:47.402962537 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-9.c	2024-11-11 12:51:19.973505232 +0100
@@ -0,0 +1,28 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c23 -pedantic" } */
+/* { dg-add-options float64x } */
+/* { dg-require-effective-target float64x } */
+
+_Complex _Float64x a = 1.if64x;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x b = 2.F64xj;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x c = 3.f64xi;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x d = 4.JF64x;	/* { dg-warning "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float64x e = 1.if64x;
+__extension__ _Complex _Float64x f = 2.F64xj;
+__extension__ _Complex _Float64x g = 3.f64xi;
+__extension__ _Complex _Float64x h = 4.JF64x;
+
+int
+main ()
+{
+  if (a * a != -1.f64x
+      || b * b != -4.f64x
+      || c * c != -9.f64x
+      || d * d != -16.f64x
+      || e * e != -1.f64x
+      || f * f != -4.f64x
+      || g * g != -9.f64x
+      || h * h != -16.f64x)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c23-imaginary-constants-10.c.jj	2024-11-11 12:50:47.402962537 +0100
+++ gcc/testsuite/gcc.dg/c23-imaginary-constants-10.c	2024-11-11 12:51:29.203375648 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are diagnosed in C23 mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c23 -pedantic-errors" } */
+/* { dg-add-options float64x } */
+/* { dg-require-effective-target float64x } */
+
+_Complex _Float64x a = 1.if64x;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x b = 2.F64xj;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x c = 3.f64xi;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+_Complex _Float64x d = 4.JF64x;	/* { dg-error "imaginary constants are a C2Y feature or GCC extension" } */
+__extension__ _Complex _Float64x e = 1.if64x;
+__extension__ _Complex _Float64x f = 2.F64xj;
+__extension__ _Complex _Float64x g = 3.f64xi;
+__extension__ _Complex _Float64x h = 4.JF64x;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-1.c.jj	2024-11-11 12:15:00.527108896 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-1.c	2024-11-11 12:42:08.397249514 +0100
@@ -0,0 +1,5 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c2y -pedantic" } */
+
+#include "c23-imaginary-constants-1.c"
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-2.c.jj	2024-11-11 12:13:31.970352710 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-2.c	2024-11-11 12:36:13.820227869 +0100
@@ -0,0 +1,28 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+
+_Complex float a = 1.if;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex float b = 2.Fj;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex float c = 3.fI;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex float d = 4.JF;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex double e = 1.i;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex double f = 2.j;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex double g = 3.I;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex double h = 4.J;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex long double i = 1.il;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex long double j = 2.Lj;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex long double k = 3.lI;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex long double l = 4.JL;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+__extension__ _Complex float m = 1.if;
+__extension__ _Complex float n = 2.Fj;
+__extension__ _Complex float o = 3.fI;
+__extension__ _Complex float p = 4.JF;
+__extension__ _Complex double q = 1.i;
+__extension__ _Complex double r = 2.j;
+__extension__ _Complex double s = 3.I;
+__extension__ _Complex double t = 4.J;
+__extension__ _Complex long double u = 1.il;
+__extension__ _Complex long double v = 2.Lj;
+__extension__ _Complex long double w = 3.lI;
+__extension__ _Complex long double x = 4.JL;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-3.c.jj	2024-11-11 12:29:04.412257788 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-3.c	2024-11-11 12:42:18.909101923 +0100
@@ -0,0 +1,11 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c2y -pedantic" } */
+/* { dg-add-options float32 } */
+/* { dg-add-options float64 } */
+/* { dg-add-options float32x } */
+/* { dg-require-effective-target float32 } */
+/* { dg-require-effective-target float32x } */
+/* { dg-require-effective-target float64 } */
+
+#include "c23-imaginary-constants-3.c"
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-4.c.jj	2024-11-11 12:30:02.318444602 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-4.c	2024-11-11 12:37:13.018396711 +0100
@@ -0,0 +1,34 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+/* { dg-add-options float32 } */
+/* { dg-add-options float64 } */
+/* { dg-add-options float32x } */
+/* { dg-require-effective-target float32 } */
+/* { dg-require-effective-target float32x } */
+/* { dg-require-effective-target float64 } */
+
+_Complex _Float32 a = 1.if32;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32 b = 2.F32j;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32 c = 3.f32i;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32 d = 4.JF32;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64 e = 1.if64;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64 f = 2.F64j;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64 g = 3.f64i;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64 h = 4.JF64;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32x i = 1.if32x;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32x j = 2.F32xj;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32x k = 3.f32xI;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float32x l = 4.JF32x;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+__extension__ _Complex _Float32 m = 1.if32;
+__extension__ _Complex _Float32 n = 2.F32j;
+__extension__ _Complex _Float32 o = 3.f32i;
+__extension__ _Complex _Float32 p = 4.JF32;
+__extension__ _Complex _Float64 q = 1.if64;
+__extension__ _Complex _Float64 r = 2.F64j;
+__extension__ _Complex _Float64 s = 3.f64i;
+__extension__ _Complex _Float64 t = 4.JF64;
+__extension__ _Complex _Float32x u = 1.if32x;
+__extension__ _Complex _Float32x v = 2.F32xj;
+__extension__ _Complex _Float32x w = 3.f32xI;
+__extension__ _Complex _Float32x x = 4.JF32x;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-5.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-5.c	2024-11-11 12:53:08.874976789 +0100
@@ -0,0 +1,7 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c2y -pedantic" } */
+/* { dg-add-options float128 } */
+/* { dg-require-effective-target float128 } */
+
+#include "c23-imaginary-constants-5.c"
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-6.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-6.c	2024-11-11 12:53:42.476505229 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+/* { dg-add-options float128 } */
+/* { dg-require-effective-target float128 } */
+
+_Complex _Float128 a = 1.if128;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float128 b = 2.F128j;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float128 c = 3.f128i;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float128 d = 4.JF128;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+__extension__ _Complex _Float128 e = 1.if128;
+__extension__ _Complex _Float128 f = 2.F128j;
+__extension__ _Complex _Float128 g = 3.f128i;
+__extension__ _Complex _Float128 h = 4.JF128;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-7.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-7.c	2024-11-11 12:54:27.724870224 +0100
@@ -0,0 +1,7 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c2y -pedantic" } */
+/* { dg-add-options float16 } */
+/* { dg-require-effective-target float16 } */
+
+#include "c23-imaginary-constants-7.c"
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-8.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-8.c	2024-11-11 12:54:34.792771033 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+/* { dg-add-options float16 } */
+/* { dg-require-effective-target float16 } */
+
+_Complex _Float16 a = 1.if16;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float16 b = 2.F16j;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float16 c = 3.f16i;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float16 d = 4.JF16;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+__extension__ _Complex _Float16 e = 1.if16;
+__extension__ _Complex _Float16 f = 2.F16j;
+__extension__ _Complex _Float16 g = 3.f16i;
+__extension__ _Complex _Float16 h = 4.JF16;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-9.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-9.c	2024-11-11 12:54:44.064640914 +0100
@@ -0,0 +1,7 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=c2y -pedantic" } */
+/* { dg-add-options float64x } */
+/* { dg-require-effective-target float64x } */
+
+#include "c23-imaginary-constants-9.c"
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-10.c.jj	2024-11-11 12:54:13.799065656 +0100
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-10.c	2024-11-11 12:54:59.266427580 +0100
@@ -0,0 +1,14 @@ 
+/* Test that imaginary constants are accepted in C2Y mode: compat warnings.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c2y -Wc23-c2y-compat" } */
+/* { dg-add-options float64x } */
+/* { dg-require-effective-target float64x } */
+
+_Complex _Float64x a = 1.if64x;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64x b = 2.F64xj;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64x c = 3.f64xi;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+_Complex _Float64x d = 4.JF64x;	/* { dg-warning "imaginary constants are a C2Y feature" } */
+__extension__ _Complex _Float64x e = 1.if64x;
+__extension__ _Complex _Float64x f = 2.F64xj;
+__extension__ _Complex _Float64x g = 3.f64xi;
+__extension__ _Complex _Float64x h = 4.JF64x;
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-11.c.jj	2024-09-17 09:04:10.523093614 +0200
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-11.c	2024-11-11 13:48:09.914656788 +0100
@@ -0,0 +1,58 @@ 
+/* Test that integral imaginary constants are diagnosed in C2Y mode: -pedantic.  */
+/* { dg-do run } */
+/* { dg-options "-std=gnu2y -pedantic" } */
+
+_Complex float a = 1i;		/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex float b = 2j;		/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex float c = 3I;		/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex float d = 4J;		/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex double e = 1il;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex double f = 2Lj;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex double g = 3lI;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex double h = 4JL;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex long double i = 1ill;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex long double j = 2LLj;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex long double k = 3llI;	/* { dg-warning "imaginary constants are a GCC extension" } */
+_Complex long double l = 4JLL;	/* { dg-warning "imaginary constants are a GCC extension" } */
+__extension__ _Complex float m = 1i;
+__extension__ _Complex float n = 2j;
+__extension__ _Complex float o = 3I;
+__extension__ _Complex float p = 4J;
+__extension__ _Complex double q = 1il;
+__extension__ _Complex double r = 2Lj;
+__extension__ _Complex double s = 3lI;
+__extension__ _Complex double t = 4JL;
+__extension__ _Complex long double u = 1ill;
+__extension__ _Complex long double v = 2LLj;
+__extension__ _Complex long double w = 3llI;
+__extension__ _Complex long double x = 4JLL;
+
+int
+main ()
+{
+  if (a * a != -1.f
+      || b * b != -4.f
+      || c * c != -9.f
+      || d * d != -16.f
+      || e * e != -1.
+      || f * f != -4.
+      || g * g != -9.
+      || h * h != -16.
+      || i * i != -1.L
+      || j * j != -4.L
+      || k * k != -9.L
+      || l * l != -16.L
+      || m * m != -1.f
+      || n * n != -4.f
+      || o * o != -9.f
+      || p * p != -16.f
+      || q * q != -1.
+      || r * r != -4.
+      || s * s != -9.
+      || t * t != -16.
+      || u * u != -1.L
+      || v * v != -4.L
+      || w * w != -9.L
+      || x * x != -16.L)
+    __builtin_abort ();
+}
--- gcc/testsuite/gcc.dg/c2y-imaginary-constants-12.c.jj	2024-09-17 09:04:10.523093614 +0200
+++ gcc/testsuite/gcc.dg/c2y-imaginary-constants-12.c	2024-11-11 13:32:04.314200680 +0100
@@ -0,0 +1,28 @@ 
+/* Test that integral imaginary constants are diagnosed in C2Y mode: -pedantic-errors.  */
+/* { dg-do compile } */
+/* { dg-options "-std=gnu2y -pedantic-errors" } */
+
+_Complex float a = 1i;		/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex float b = 2j;		/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex float c = 3I;		/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex float d = 4J;		/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex double e = 1il;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex double f = 2Lj;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex double g = 3lI;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex double h = 4JL;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex long double i = 1ill;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex long double j = 2LLj;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex long double k = 3llI;	/* { dg-error "imaginary constants are a GCC extension" } */
+_Complex long double l = 4JLL;	/* { dg-error "imaginary constants are a GCC extension" } */
+__extension__ _Complex float m = 1i;
+__extension__ _Complex float n = 2j;
+__extension__ _Complex float o = 3I;
+__extension__ _Complex float p = 4J;
+__extension__ _Complex double q = 1il;
+__extension__ _Complex double r = 2Lj;
+__extension__ _Complex double s = 3lI;
+__extension__ _Complex double t = 4JL;
+__extension__ _Complex long double u = 1ill;
+__extension__ _Complex long double v = 2LLj;
+__extension__ _Complex long double w = 3llI;
+__extension__ _Complex long double x = 4JLL;