gcc/

	PR c/39037
	* c-common.h (mark_valid_location_for_stdc_pragma,
	valid_location_for_stdc_pragma_p, set_float_const_decimal64,
	clear_float_const_decimal64, float_const_decimal64_p): New.
	* c.opt (Wunsuffixed-float-constants): New.
	* c-lex.c (interpret_float): Use pragma FLOAT_CONST_DECIMAL64 for
	unsuffixed float constant, handle new warning.
	* c-cppbuiltin.c (c_cpp_builtins): Use cast for double constants.
	* c-decl.c (c_scope): New flag float_const_decimal64.
	(set_float_const_decimal64, clear_float_const_decimal64,
	float_const_decimal64_p): New.
	(push_scope): Set new flag.
	* c-parser.c (c_parser_translation_unit): Mark when it's valid
	to use STDC pragmas.
	(c_parser_external_declaration): Ditto.
	(c_parser_compound_statement_nostart): Ditto.
	* c-pragma.c (valid_location_for_stdc_pragma,
	mark_valid_location_for_stdc_pragma,
	valid_location_for_stdc_pragma_p, handle_stdc_pragma,
	handle_pragma_float_const_decimal64): New.
	(init_pragma): Register new pragma FLOAT_CONST_DECIMAL64.
	* cp/semantics.c (valid_location_for_stdc_pragma_p,
	set_float_const_decimal64, clear_float_const_decimal64,
	float_const_decimal64_p): New dummy functions.
	* doc/extend.texi (Decimal Float): Remove statement that the
	pragma, and suffix for double constants, are not supported.
	* doc/invoke.texi (Warning Options): List new option.
	(-Wunsuffixed-float-constants): New.

gcc/testsuite
	PR c/39037
	* gcc.dg/Wunsuffixed-float-constants-1.c: New test.
	* gcc.dg/cpp/pragma-float-const-decimal64-1.c: New test.
	* gcc.dg/dfp/float-constant-double.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-1.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-2.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-3.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-4.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-5.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-6.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-7.c: New test.
	* gcc.dg/dfp/pragma-float-const-decimal64-8.c: New test.
	* g++.dg/cpp/pragma-float-const-decimal64-1.C: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@147259 138bc75d-0d04-0410-961f-82ee72b054a4

9 files changed, 626 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/dfp/float-constant-double.c b/gcc/testsuite/gcc.dg/dfp/float-constant-double.c
new file mode 100644
index 00000000000..3f8de656bf6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/float-constant-double.c
@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99" } */
+
+/* Constant float values of type double in <float.h> are suffixed with L
+   and cast to double so they can be used within code that uses pragma
+   FLOAT_CONST_DECIMAL64.  If they were not suffixed then use of the macro
+   would have them interpreted as _Decimal64, leading to errors when used
+   in expressions with other operands of type double.  */
+
+#include <float.h>
+
+extern double a, b, c, d;
+
+void
+foo ()
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")
+  a = 0.1d * DBL_MAX;
+  b = DBL_EPSILON * 10.0d;
+  c = DBL_MIN * 200.0d;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-1.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-1.c
new file mode 100644
index 00000000000..79fabf34484
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-1.c
@@ -0,0 +1,85 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -Wall" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Verify that the pragma has the expected result by using unsuffixed
+   float constants as operands in expressions that would mix binary and
+   decimal operands if the pragma had no effect, or the wrong effect.  */
+
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+double a = 1.0 * 2.0dd;
+
+double
+f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  double b = 2.0 * 3.0d;
+
+  {
+    double c = 3.0 * 4.0d;
+    b = b + c;
+  }
+
+  {
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+    double d = 4.0 * 5.0dd;
+
+    b = b + d;
+  }
+
+  {
+     /* Default is OFF.  */
+#pragma STDC FLOAT_CONST_DECIMAL64 DEFAULT
+     double e = 5.0 * 6.0d;
+     b = b + e;
+  }
+
+  return b;
+}
+
+double
+f2 (void)
+{
+  /* Use value from outer scope, which is ON.  */
+  double b = 2.0 * 3.0dd;
+
+  {
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+    double c = 3.0 * 4.0d;
+
+    {
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+      double d = 4.0 * 5.0dd;
+
+      {
+#pragma STDC FLOAT_CONST_DECIMAL64 DEFAULT
+	double e = 5.0 * 6.0d;
+
+	{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+	  double f = 6.0 * 7.0dd;
+
+	  b = a + b + c + d + e + f;
+	}
+      }
+    }
+  }
+  return b;
+}
+
+/* Use previous value from this scope, which is ON.  */
+double f = 6.0 * 7.0dd;
+
+double
+f3 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  double b = 2.0 * 3.0d;
+
+  return b + f;
+}
+
+/* Return to the state from this scope, which is ON.  */
+double g = 7.0 + 8.0dd;
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-2.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-2.c
new file mode 100644
index 00000000000..212748c6c78
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-2.c
@@ -0,0 +1,86 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -Wall" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Verify that the pragma has the expected result by using unsuffixed
+   float constants as operands in expressions that would mix binary and
+   decimal operands if the pragma had no effect, or the wrong effect.
+   Use _Pragma rather than #pragma.  */
+
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")
+double a = 1.0 * 2.0dd;
+
+double
+f1 (void)
+{
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 OFF")
+  double b = 2.0 * 3.0d;
+
+  {
+    double c = 3.0 * 4.0d;
+    b = b + c;
+  }
+
+  {
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")
+    double d = 4.0 * 5.0dd;
+
+    b = b + d;
+  }
+
+  {
+     /* Default is OFF.  */
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 DEFAULT")
+     double e = 5.0 * 6.0d;
+     b = b + e;
+  }
+
+  return b;
+}
+
+double
+f2 (void)
+{
+  /* Use value from outer scope, which is ON.  */
+  double b = 2.0 * 3.0dd;
+
+  {
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 OFF")
+    double c = 3.0 * 4.0d;
+
+    {
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")
+      double d = 4.0 * 5.0dd;
+
+      {
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 DEFAULT")
+	double e = 5.0 * 6.0d;
+
+	{
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")
+	  double f = 6.0 * 7.0dd;
+
+	  b = a + b + c + d + e + f;
+	}
+      }
+    }
+  }
+  return b;
+}
+
+/* Use previous value from this scope, which is ON.  */
+double f = 6.0 * 7.0dd;
+
+double
+f3 (void)
+{
+_Pragma ("STDC FLOAT_CONST_DECIMAL64 OFF")
+  double b = 2.0 * 3.0d;
+
+  return b + f;
+}
+
+/* Return to the state from this scope, which is ON.  */
+double g = 7.0 + 8.0dd;
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-3.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-3.c
new file mode 100644
index 00000000000..b9286aac11a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-3.c
@@ -0,0 +1,83 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -Wall" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).  */
+
+/* Check that defining macros whose names are the same as the tokens used
+   in the pragma doesn't affect use of the pragma.  */
+
+#define ON YES
+#define OFF NO
+#define DEFAULT NOPE
+#define STDC OFFICIAL
+#define FLOAT_CONST_DECIMAL64 NEW_PRAGMA
+
+double a;
+
+void
+f1a (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+  a = 1.0dd + 2.0;
+}
+
+void
+f1b (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  a = 2.0d + 3.0;
+}
+
+void
+f1c (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 DEFAULT
+  a = 3.0d + 4.0;
+}
+
+/* Check that a macro can be used for the entire pragma.  */
+
+#define PRAGMA(x) _Pragma (#x)
+#define DEFAULT_FLOAT_IS_DECIMAL PRAGMA(STDC FLOAT_CONST_DECIMAL64 ON)
+#define DEFAULT_FLOAT_IS_BINARY PRAGMA(STDC FLOAT_CONST_DECIMAL64 OFF)
+
+void
+f2a (void)
+{
+  DEFAULT_FLOAT_IS_DECIMAL
+  a = 5.0 * 6.0dd;
+}
+
+void
+f2b (void)
+{
+  DEFAULT_FLOAT_IS_BINARY
+  a = 6.0 * 7.0d;
+}
+
+/* _Pragma can be used with macros, including the use of a macro for the
+    switch.  */
+
+#undef ON
+#undef OFF
+#undef DEFAULT
+#undef STDC
+#undef FLOAT_CONST_DECIMAL64
+
+#define SWITCH ON
+#define FLOAT_CONST_DECIMAL64(x) PRAGMA(STDC FLOAT_CONST_DECIMAL64 x)
+
+void
+f3a (void)
+{
+  FLOAT_CONST_DECIMAL64(SWITCH)
+  a = 1.0 * 7.0dd;
+}
+
+void
+f3b (void)
+{
+  FLOAT_CONST_DECIMAL64(OFF)
+  a = 1.0 + 2.0d;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-4.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-4.c
new file mode 100644
index 00000000000..86cec1dbd45
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-4.c
@@ -0,0 +1,46 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Check that malformed versions of pragma STDC FLOAT_CONST_DECIMAL64
+   are detected.  */
+
+double a;
+
+void f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64	/* { dg-warning "malformed" } */
+  a = 1.0;
+}
+
+void f2 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 DFP	/* { dg-warning "malformed" } */
+  a = 2.0;
+}
+
+void f3 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON DFP /* { dg-warning "junk at end" } */
+  a = 3.0;
+}
+
+void f4 (void)
+{
+  _Pragma ( "STDC FLOAT_CONST_DECIMAL64" )	/* { dg-warning "malformed" } */
+  a = 1.0;
+}
+
+void f5 (void)
+{
+  _Pragma ( "STDC FLOAT_CONST_DECIMAL64 DFP" )	/* { dg-warning "malformed" } */
+  a = 2.0;
+}
+
+void f6 (void)
+{
+  _Pragma ( "STDC FLOAT_CONST_DECIMAL64 ON DFP" ) /* { dg-warning "junk at end" } */
+  a = 3.0;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-5.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-5.c
new file mode 100644
index 00000000000..75e9525dda0
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-5.c
@@ -0,0 +1,46 @@
+/* { dg-do compile } */
+/* { dg-options "-std=c99 -pedantic" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Check that there is a pedantic warning for the use of pragma
+   STD FLOAT_CONST_DECIMAL64.  */
+
+double a;
+
+void f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON		/* { dg-warning "ISO C" } */
+  a = 1.0;
+}
+
+void f2 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF		/* { dg-warning "ISO C" } */
+  a = 2.0;
+}
+
+void f3 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 DEFAULT	/* { dg-warning "ISO C" } */
+  a = 3.0;
+}
+
+void f4 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")	/* { dg-warning "ISO C" } */
+  a = 1.0;
+}
+
+void f5 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 OFF")	/* { dg-warning "ISO C" } */
+  a = 2.0;
+}
+
+void f6 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 DEFAULT")	/* { dg-warning "ISO C" } */
+  a = 3.0;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-6.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-6.c
new file mode 100644
index 00000000000..03c1715bee6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-6.c
@@ -0,0 +1,46 @@
+/* { dg-do compile } */
+/* { dg-options "-std=c99 -pedantic-errors" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Check that there is a pedantic error for the use of pragma
+   STD FLOAT_CONST_DECIMAL64.  */
+
+double a;
+
+void f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON		/* { dg-error "ISO C" } */
+  a = 1.0;
+}
+
+void f2 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF		/* { dg-error "ISO C" } */
+  a = 2.0;
+}
+
+void f3 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 DEFAULT	/* { dg-error "ISO C" } */
+  a = 3.0;
+}
+
+void f4 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 ON")	/* { dg-error "ISO C" } */
+  a = 1.0;
+}
+
+void f5 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 OFF")	/* { dg-error "ISO C" } */
+  a = 2.0;
+}
+
+void f6 (void)
+{
+  _Pragma ("STDC FLOAT_CONST_DECIMAL64 DEFAULT") /* { dg-error "ISO C" } */
+  a = 3.0;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-7.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-7.c
new file mode 100644
index 00000000000..7533ee7f0de
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-7.c
@@ -0,0 +1,39 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -Wall" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Check that when pragma FLOAT_CONST_DECIMAL64 is in effect so that
+   unsuffixed constants are _Decimal64, invalid types are still reported
+   as invalid.  */
+
+double
+f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  double a = 0x1.0p1;
+  double b = 1.0i;
+
+  return a + b;
+}
+
+double
+f2 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  double a = 0x1.0p1dd;		/* { dg-error "with hex" } */
+  double b = 1.0idd;		/* { dg-error "invalid suffix" } */
+
+  return a + b;
+}
+
+double
+f3 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+  double a = 0x1.0p1;	/* Hex constant is not affected by pragma.  */
+  double b = 1.0i;	/* Imaginary constant is not affected by pragma.  */
+
+  return a + b;
+}
diff --git a/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-8.c b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-8.c
new file mode 100644
index 00000000000..5dbbda5b8f2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/dfp/pragma-float-const-decimal64-8.c
@@ -0,0 +1,174 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -Wall" } */
+
+/* N1312 7.1.1: The FLOAT_CONST_DECIMAL64 pragma.
+   C99 6.4.4.2a (New).
+
+   Pragma STDC FLOAT_CONST_DECIMAL64 "shall occur either outside external
+   declarations or preceding all explicit declarations and statements
+   inside a compound statement." */
+
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+
+#define MAX 200
+
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+
+double a;
+
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+
+struct S1 {
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  int i;
+  int j;
+};
+
+struct S2 {
+  int i;
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  int j;
+};
+
+struct S3 {
+  int i;
+  int j;
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+};
+
+enum E1 {
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-error "#pragma" } */
+  one,
+  two
+};
+
+enum E2 {
+  red,
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-error "#pragma" } */
+  blue
+};
+
+enum E3 {
+  cat,
+  dog
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-error "#pragma" } */
+};
+
+double
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF	/* { dg-error "#pragma" } */
+b;
+
+double
+f1 (void)
+{
+#pragma STDC FLOAT_CONST_DECIMAL64 ON
+  return a;
+}
+
+double
+f2 (void)
+{
+  double b;
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  b = 0.5;
+  return a + b;
+}
+
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+
+double
+f3 (void)
+{
+  typedef double b32;
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  b32 b = 0.5;
+  return b;
+}
+
+double
+f4 (int i)
+{
+top:
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF	/* { dg-warning "invalid location" } */
+  if (i == 0)
+    return a;  
+  a *= 2.;
+  i = 0;
+  goto top;
+}
+
+double
+f5 (int i)
+{
+  a = a * i;
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF	/* { dg-warning "invalid location" } */
+  return a * 2.;
+}
+
+double
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-error "#pragma" } */
+f6 (void)
+{
+  return a;
+}
+
+double
+f7
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-error "#pragma" } */
+(void)					/* { dg-error "before" } */
+{
+  return a;
+}
+
+double
+f8 (void)
+{
+  {
+#pragma STDC FLOAT_CONST_DECIMAL64 OFF
+  }
+#pragma STDC FLOAT_CONST_DECIMAL64 ON   /* { dg-warning "invalid location" } */
+  return a;
+}
+
+extern void foo9 (void *);
+
+double
+f9 (void)
+{
+  __label__ here;
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  foo9 (&&here);
+here:
+  return a;
+}
+
+double
+f10 (void)
+{
+  void foo10 (void)
+  {
+    a = 1.0;
+  }
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  return a;
+}
+
+double
+f11 (void)
+{
+  __extension__
+   struct A {
+    struct { char a; };
+    char b;
+  };
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  return a;
+}
+
+double
+f12 (void)
+{
+  __extension__ ({ a = 0.5; });
+#pragma STDC FLOAT_CONST_DECIMAL64 ON	/* { dg-warning "invalid location" } */
+  return a;
+}