PR tree-optimization/78696 - [7 Regression] -fprintf-return-value misoptimizes %.Ng where N is greater than 10

gcc/ChangeLog:

	PR tree-optimization/78696
	* gimple-ssa-sprintf.c (format_floating): Correct handling of
	precision.  Use MPFR for %f for greater fidelity.  Correct handling
	of %g.
	(pass_sprintf_length::compute_format_length): Set width and precision
	specified by asrerisk to void_node for vararg functions.
	(try_substitute_return_value): Adjust dump output.

gcc/testsuite/ChangeLog:

	PR tree-optimization/78696
	* gcc.dg/tree-ssa/builtin-sprintf-5.c: Add test cases.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-7.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf.c (checkv): Add test cases.

diff --git a/gcc/gimple-ssa-sprintf.c b/gcc/gimple-ssa-sprintf.c
index 8de9a1e..3d34342 100644
--- a/gcc/gimple-ssa-sprintf.c
+++ b/gcc/gimple-ssa-sprintf.c
@@ -474,9 +474,11 @@ struct conversion_spec
   /* Numeric precision as in "%.32s".  */
   int precision;
 
-  /* Width specified via the '*' character.  */
+  /* Width specified via the '*' character.  Need not be INTEGER_CST.
+     For vararg functions set to void_node.  */
   tree star_width;
-  /* Precision specified via the asterisk.  */
+  /* Precision specified via the asterisk.  Need not be INTEGER_CST.
+     For vararg functions set to void_node.  */
   tree star_precision;
 
   /* Length modifier.  */
@@ -1135,10 +1137,11 @@ format_integer (const conversion_spec &spec, tree arg)
 }
 
 /* Return the number of bytes to format using the format specifier
-   SPEC the largest value in the real floating TYPE.  */
+   SPEC and the precision PREC the largest value in the real floating
+   TYPE.  */
 
 static int
-format_floating_max (tree type, char spec, int prec = -1)
+format_floating_max (tree type, char spec, int prec)
 {
   machine_mode mode = TYPE_MODE (type);
 
@@ -1189,7 +1192,6 @@ static fmtresult
 format_floating (const conversion_spec &spec, int width, int prec)
 {
   tree type;
-  bool ldbl = false;
 
   switch (spec.modifier)
     {
@@ -1200,12 +1202,10 @@ format_floating (const conversion_spec &spec, int width, int prec)
 
     case FMT_LEN_L:
       type = long_double_type_node;
-      ldbl = true;
       break;
 
     case FMT_LEN_ll:
       type = long_double_type_node;
-      ldbl = true;
       break;
 
     default:
@@ -1215,19 +1215,20 @@ format_floating (const conversion_spec &spec, int width, int prec)
   /* The minimum and maximum number of bytes produced by the directive.  */
   fmtresult res;
 
-  /* Log10 of of the maximum number of exponent digits for the type.  */
-  int logexpdigs = 2;
+  /* The result is always bounded (though the range may be all of int).  */
+  res.bounded = true;
 
-  if (REAL_MODE_FORMAT (TYPE_MODE (type))->b == 2)
-    {
-      /* The base in which the exponent is represented should always
-	 be 2 in GCC.  */
-
-      const double log10_2 = .30102999566398119521;
+  /* The minimum output as determined by flags.  It's always at least 1.  */
+  int flagmin = (1 /* for the first digit */
+		 + (spec.get_flag ('+') | spec.get_flag (' '))
+		 + (prec == 0 && spec.get_flag ('#')));
 
-      /* Compute T_MAX_EXP for base 2.  */
-      int expdigs = REAL_MODE_FORMAT (TYPE_MODE (type))->emax * log10_2;
-      logexpdigs = ilog (expdigs, 10);
+  if (width == INT_MIN || prec == INT_MIN)
+    {
+      /* When either width or precision is specified but unknown
+	 the upper bound is the maximum.  Otherwise it will be
+	 computed for each directive below.  */
+      res.range.max = target_int_max ();
     }
 
   switch (spec.specifier)
@@ -1235,75 +1236,73 @@ format_floating (const conversion_spec &spec, int width, int prec)
     case 'A':
     case 'a':
       {
-	/* The minimum output is "0x.p+0".  */
-	res.range.min = 6 + (prec > 0 ? prec : 0);
-	res.range.max = (width == INT_MIN
-			 ? HOST_WIDE_INT_MAX
-			 : format_floating_max (type, 'a', prec));
-
-	/* The output of "%a" is fully specified only when precision
-	   is explicitly specified and width isn't unknown.  */
-	res.bounded = INT_MIN != width && -1 < prec;
+	/* The minimum output is "0xp+0".  */
+	res.range.min = flagmin + 5 + (prec > 0 ? prec + 1 : 0);
+	if (res.range.max == HOST_WIDE_INT_MAX)
+	  {
+	    /* Compute the upper bound for -TYPE_MAX.  */
+	    res.range.max = format_floating_max (type, 'a', prec);
+	  }
+
 	break;
       }
 
     case 'E':
     case 'e':
       {
-	bool sign = spec.get_flag ('+') || spec.get_flag (' ');
 	/* The minimum output is "[-+]1.234567e+00" regardless
 	   of the value of the actual argument.  */
-	res.range.min = (sign
-			 + 1 /* unit */ + (prec < 0 ? 7 : prec ? prec + 1 : 0)
+	res.range.min = (flagmin
+			 + (prec == INT_MIN
+			    ? 0 : prec < 0 ? 7 : prec ? prec + 1 : 0)
 			 + 2 /* e+ */ + 2);
-	/* Unless width is uknown the maximum output is the minimum plus
-	   sign (unless already included), plus the difference between
-	   the minimum exponent of 2 and the maximum exponent for the type.  */
-	res.range.max = (width == INT_MIN
-			 ? HOST_WIDE_INT_M1U
-			 : res.range.min + !sign + logexpdigs - 2);
-
-	/* "%e" is fully specified and the range of bytes is bounded
-	   unless width is unknown.  */
-	res.bounded = INT_MIN != width;
+
+	if (res.range.max == HOST_WIDE_INT_MAX)
+	  {
+	    /* MPFR uses a precision of 16 by default for some reason.
+	       Set it to the C default of 6.  */
+	    res.range.max = format_floating_max (type, 'e',
+						 -1 == prec ? 6 : prec);
+	  }
 	break;
       }
 
     case 'F':
     case 'f':
       {
-	/* The minimum output is "1.234567" regardless of the value
-	   of the actual argument.  */
-	res.range.min = 2 + (prec < 0 ? 6 : prec);
-
-	/* Compute the maximum just once.  */
-	const int f_max[] = {
-	  format_floating_max (double_type_node, 'f', prec),
-	  format_floating_max (long_double_type_node, 'f', prec)
-	};
-	res.range.max = width == INT_MIN ? HOST_WIDE_INT_MAX : f_max [ldbl];
-
-	/* "%f" is fully specified and the range of bytes is bounded
-	   unless width is unknown.  */
-	res.bounded = INT_MIN != width;
+	/* The lower bound when precision isn't specified is 8 bytes
+	   ("1.23456" since precision is taken to be 6).  When precision
+	   is zero, the lower bound is 1 byte (e.g., "1").  Otherwise,
+	   when precision is greater than zero, then the lower bound
+	   is 2 plus precision (plus flags).  */
+	res.range.min = (flagmin
+			 + (prec != INT_MIN)   /* for decimal point */
+			 + (prec == INT_MIN
+			    ? 0 : prec < 0 ? 6 : prec ? prec : -1));
+
+	if (res.range.max == HOST_WIDE_INT_MAX)
+	  {
+	    /* Compute the upper bound for -TYPE_MAX.  */
+	    res.range.max = format_floating_max (type, 'f', prec);
+	  }
 	break;
       }
+
     case 'G':
     case 'g':
       {
-	/* The minimum is the same as for '%F'.  */
-	res.range.min = 2 + (prec < 0 ? 6 : prec);
-
-	/* Compute the maximum just once.  */
-	const int g_max[] = {
-	  format_floating_max (double_type_node, 'g', prec),
-	  format_floating_max (long_double_type_node, 'g', prec)
-	};
-	res.range.max = width == INT_MIN ? HOST_WIDE_INT_MAX : g_max [ldbl];
+	/* The %g output depends on precision and the exponent of
+	   the argument.  Since the value of the argument isn't known
+	   the lower bound on the range of bytes (not counting flags
+	   or width) is 1.  */
+	res.range.min = flagmin;
 
-	/* "%g" is fully specified and the range of bytes is bounded
-	   unless width is unknown.  */
-	res.bounded = INT_MIN != width;
+	if (res.range.max == HOST_WIDE_INT_MAX)
+	  {
+	    /* Compute the upper bound for -TYPE_MAX which should be
+	       the lesser of %e and %f.  */
+	    res.range.max = format_floating_max (type, 'g', prec);
+	  }
 	break;
       }
 
@@ -1313,6 +1312,7 @@ format_floating (const conversion_spec &spec, int width, int prec)
 
   if (width > 0)
     {
+      /* If width has been specified use it to adjust the range.  */
       if (res.range.min < (unsigned)width)
 	res.range.min = width;
       if (res.range.max < (unsigned)width)
@@ -1360,11 +1360,7 @@ format_floating (const conversion_spec &spec, tree arg)
       if (TREE_CODE (spec.star_precision) == INTEGER_CST)
 	prec = tree_to_shwi (spec.star_precision);
       else
-	{
-	  /* FIXME: Handle non-constant precision.  */
-	  res.range.min = res.range.max = HOST_WIDE_INT_M1U;
-	  return res;
-	}
+	prec = INT_MIN;
     }
   else if (res.constant && TOUPPER (spec.specifier) != 'A')
     {
@@ -1375,11 +1371,6 @@ format_floating (const conversion_spec &spec, tree arg)
 
   if (res.constant)
     {
-      /* Set up an array to easily iterate over.  */
-      unsigned HOST_WIDE_INT* const minmax[] = {
-	&res.range.min, &res.range.max
-      };
-
       /* Get the real type format desription for the target.  */
       const REAL_VALUE_TYPE *rvp = TREE_REAL_CST_PTR (arg);
       const real_format *rfmt = REAL_MODE_FORMAT (TYPE_MODE (TREE_TYPE (arg)));
@@ -1418,16 +1409,32 @@ format_floating (const conversion_spec &spec, tree arg)
       *pfmt++ = spec.specifier;
       *pfmt = '\0';
 
-      for (int i = 0; i != sizeof minmax / sizeof *minmax; ++i)
+      {
+	/* Set up an array to easily iterate over below.  */
+	unsigned HOST_WIDE_INT* const minmax[] = {
+	  &res.range.min, &res.range.max
+	};
+
+	for (int i = 0; i != sizeof minmax / sizeof *minmax; ++i)
+	  {
+	    /* Use the MPFR rounding specifier to round down in the first
+	       iteration and then up.  In most but not all cases this will
+	       result in the same number of bytes.  */
+	    *rndspec = "DU"[i];
+
+	    /* Format it and store the result in the corresponding
+	       member of the result struct.  */
+	    *minmax[i] = mpfr_snprintf (NULL, 0, fmtstr, mpfrval);
+	  }
+      }
+
+      /* Make sure the minimum is less than the maximum (MPFR rounding
+	 in the call to mpfr_snprintf can result in the reverse.  */
+      if (res.range.max < res.range.min)
 	{
-	  /* Use the MPFR rounding specifier to round down in the first
-	     iteration and then up.  In most but not all cases this will
-	     result in the same number of bytes.  */
-	  *rndspec = "DU"[i];
-
-	  /* Format it and store the result in the corresponding
-	     member of the result struct.  */
-	  *minmax[i] = mpfr_snprintf (NULL, 0, fmtstr, mpfrval);
+	  unsigned HOST_WIDE_INT tmp = res.range.min;
+	  res.range.min = res.range.max;
+	  res.range.max = tmp;
 	}
 
       /* The range of output is known even if the result isn't bounded.  */
@@ -2263,10 +2270,10 @@ pass_sprintf_length::compute_format_length (const call_info &info,
 	{
 	  /* Similarly to the block above, this could be either a POSIX
 	     positional argument or a width, depending on what follows.  */
-	  if (gimple_call_num_args (info.callstmt) <= argno)
-	    return false;
-
-	  spec.star_width = gimple_call_arg (info.callstmt, argno++);
+	  if (argno < gimple_call_num_args (info.callstmt))
+	    spec.star_width = gimple_call_arg (info.callstmt, argno++);
+	  else
+	    spec.star_width = void_node;
 	  ++pf;
 	}
 
@@ -2342,7 +2349,10 @@ pass_sprintf_length::compute_format_length (const call_info &info,
 	    }
 	  else if ('*' == *pf)
 	    {
-	      spec.star_width = gimple_call_arg (info.callstmt, argno++);
+	      if (argno < gimple_call_num_args (info.callstmt))
+		spec.star_width = gimple_call_arg (info.callstmt, argno++);
+	      else
+		spec.star_width = void_node;
 	      ++pf;
 	    }
 	  else if ('\'' == *pf)
@@ -2370,7 +2380,10 @@ pass_sprintf_length::compute_format_length (const call_info &info,
 	    }
 	  else if ('*' == *pf)
 	    {
-	      spec.star_precision = gimple_call_arg (info.callstmt, argno++);
+	      if (argno < gimple_call_num_args (info.callstmt))
+		spec.star_precision = gimple_call_arg (info.callstmt, argno++);
+	      else
+		spec.star_precision = void_node;
 	      ++pf;
 	    }
 	  else
@@ -2629,11 +2642,11 @@ try_substitute_return_value (gimple_stmt_iterator *gsi,
 	    fprintf (dump_file,
 		     " %s-bounds return value in range [%lu, %lu]%s.\n",
 		     inbounds,
-		     (unsigned long)res.number_chars_min,
-		     (unsigned long)res.number_chars_max, ign);
+		     (unsigned long)res.number_chars_min - 1,
+		     (unsigned long)res.number_chars_max - 1, ign);
 	  else
 	    fprintf (dump_file, " %s-bounds return value %lu%s.\n",
-		     inbounds, (unsigned long)res.number_chars, ign);
+		     inbounds, (unsigned long)res.number_chars - 1, ign);
 	}
     }
 }
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-5.c b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-5.c
index dbb0dd9..bec6e09 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-5.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-5.c
@@ -19,6 +19,7 @@
       FAIL (__LINE__)(value);			\
   } while (0)
 
+/* Verify that EXPECT == snprintf(0, 0, ...).  */
 #define T(expect, ...)					\
   do {							\
     int n = __builtin_snprintf (0, 0, __VA_ARGS__);	\
@@ -108,6 +109,7 @@ void test_arg_multiarg (int i, double d)
   T (16, "%*i %s", 12, i, "abc");
 }
 
+/* Verify that EXPECT == vsnprintf(0, 0, ...).  */
 #define TV(expect, fmt, va)				\
   do {							\
     int n = __builtin_vsnprintf (0, 0, fmt, va);	\
@@ -117,9 +119,7 @@ void test_arg_multiarg (int i, double d)
 void test_va_int (__builtin_va_list va)
 {
   TV ( 2, "%02hhx", va);
-  TV ( 2, "%02.*hhx", va);
   TV ( 4, "%04hx", va);
-  TV ( 4, "%04.*hx", va);
 }
 
 void test_va_multiarg (__builtin_va_list va)
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-7.c b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-7.c
new file mode 100644
index 0000000..c8c6405
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-7.c
@@ -0,0 +1,276 @@
+/* 78696 - -fprintf-return-value misoptimizes %.Ng where N is greater than 10
+   Test to verify the correctness of ranges of output computed for floating
+   point directives.
+   { dg-do compile }
+   { dg-options "-O2 -Wformat -Wformat-length -ftrack-macro-expansion=0" } */
+
+typedef __builtin_va_list va_list;
+
+char dst[1];
+
+extern void sink (int, void*);
+
+/* Macro to test either width or precision specified by the asterisk
+   (but not both).  */
+#define T1(fmt, a)    sink (__builtin_sprintf (dst + 1, fmt, a, x), dst)
+
+/* Macro to test both width and precision specified by the asterisk.  */
+#define T2(fmt, w, p) sink (__builtin_sprintf (dst + 1, fmt, w, p, x), dst)
+
+/* Macro to test vsprintf with both width and precision specified by
+   the asterisk.  */
+#define T(fmt) sink (__builtin_vsprintf (dst + 1, fmt, va), dst)
+
+/* Exercise %a.  */
+void test_a (int w, int p, double x)
+{
+  T1 ("%.*a", 0);     /* { dg-warning "between 6 and 10 bytes" } */
+  T1 ("%.*a", 1);     /* { dg-warning "between 8 and 12 bytes" } */
+  T1 ("%.*a", 2);     /* { dg-warning "between 9 and 13 bytes" } */
+  T1 ("%.*a", 99);    /* { dg-warning "between 106 and 110 bytes" } */
+  T1 ("%.*a", 199);   /* { dg-warning "between 206 and 210 bytes" } */
+  T1 ("%.*a", 1099);  /* { dg-warning "between 1106 and 1110 bytes" } */
+
+  T1 ("%*.a", 0);     /* { dg-warning "between 6 and 10 bytes" } */
+  T1 ("%*.a", 1);     /* { dg-warning "between 6 and 10 bytes" } */
+  T1 ("%*.a", 3);     /* { dg-warning "between 6 and 10 bytes" } */
+  T1 ("%*.a", 6);     /* { dg-warning "between 6 and 10 bytes" } */
+  T1 ("%*.a", 7);     /* { dg-warning "between 7 and 10 bytes" } */
+
+  T1 ("%*.a", w);     /* { dg-warning "writing 6 or more bytes" } */
+  T1 ("%*.0a", w);    /* { dg-warning "writing 6 or more bytes" } */
+  T1 ("%*.1a", w);    /* { dg-warning "writing 8 or more bytes" } */
+  T1 ("%*.2a", w);    /* { dg-warning "writing 9 or more bytes" } */
+
+  T1 ("%.*a",  p);    /* { dg-warning "writing 6 or more bytes" } */
+  T1 ("%1.*a", p);    /* { dg-warning "writing 6 or more bytes" } */
+  T1 ("%2.*a", p);    /* { dg-warning "writing 6 or more bytes" } */
+  T1 ("%3.*a", p);    /* { dg-warning "writing 6 or more bytes" } */
+
+  T2 ("%*.*a", w, p); /* { dg-warning "writing 6 or more bytes" } */
+  T2 ("%*.*a", w, p); /* { dg-warning "writing 6 or more bytes" } */
+  T2 ("%*.*a", w, p); /* { dg-warning "writing 6 or more bytes" } */
+}
+
+/* Exercise %e.  */
+void test_e (int w, int p, double x)
+{
+  T1 ("%.*e", 0);     /* { dg-warning "between 5 and 7 bytes" } */
+  T1 ("%.*e", 1);     /* { dg-warning "between 7 and 9 bytes" } */
+  T1 ("%.*e", 2);     /* { dg-warning "between 8 and 10 bytes" } */
+  T1 ("%.*e", 99);    /* { dg-warning "between 105 and 107 bytes" } */
+  T1 ("%.*e", 199);   /* { dg-warning "between 205 and 207 bytes" } */
+  T1 ("%.*e", 1099);  /* { dg-warning "between 1105 and 1107 bytes" } */
+
+  T1 ("%*.e", 0);     /* { dg-warning "between 5 and 7 bytes" } */
+  T1 ("%*.e", 1);     /* { dg-warning "between 5 and 7 bytes" } */
+  T1 ("%*.e", 1);     /* { dg-warning "between 5 and 7 bytes" } */
+  T1 ("%*.e", 3);     /* { dg-warning "between 5 and 7 bytes" } */
+  T1 ("%*.e", 6);     /* { dg-warning "between 6 and 7 bytes" } */
+  T1 ("%*.e", 7);     /* { dg-warning "writing 7 bytes" } */
+
+  T1 ("%*.e", w);     /* { dg-warning "writing 5 or more bytes" } */
+  T1 ("%*.0e", w);    /* { dg-warning "writing 5 or more bytes" } */
+  T1 ("%*.1e", w);    /* { dg-warning "writing 7 or more bytes" } */
+  T1 ("%*.2e", w);    /* { dg-warning "writing 8 or more bytes" } */
+
+  T1 ("%.*e",  p);    /* { dg-warning "writing 5 or more bytes" } */
+  T1 ("%1.*e", p);    /* { dg-warning "writing 5 or more bytes" } */
+  T1 ("%2.*e", p);    /* { dg-warning "writing 5 or more bytes" } */
+  T1 ("%3.*e", p);    /* { dg-warning "writing 5 or more bytes" } */
+
+  T2 ("%*.*e", w, p); /* { dg-warning "writing 5 or more bytes" } */
+  T2 ("%*.*e", w, p); /* { dg-warning "writing 5 or more bytes" } */
+  T2 ("%*.*e", w, p); /* { dg-warning "writing 5 or more bytes" } */
+}
+
+/* Exercise %f.  */
+void test_f (int w, int p, double x)
+{
+  T1 ("%.*f", 0);           /* { dg-warning "between 1 and 310 bytes" } */
+  T1 ("%.*f", 1);           /* { dg-warning "between 3 and 312 bytes" } */
+  T1 ("%.*f", 2);           /* { dg-warning "between 4 and 313 bytes" } */
+  T1 ("%.*f", 99);          /* { dg-warning "between 101 and 410 bytes" } */
+  T1 ("%.*f", 199);         /* { dg-warning "between 201 and 510 bytes" } */
+  T1 ("%.*f", 1099);        /* { dg-warning "between 1101 and 1410 bytes" } */
+
+  T2 ("%*.*f", 0, 0);       /* { dg-warning "between 1 and 310 bytes" } */
+  T2 ("%*.*f", 1, 0);       /* { dg-warning "between 1 and 310 bytes" } */
+  T2 ("%*.*f", 2, 0);       /* { dg-warning "between 2 and 310 bytes" } */
+  T2 ("%*.*f", 3, 0);       /* { dg-warning "between 3 and 310 bytes" } */
+  T2 ("%*.*f", 310, 0);     /* { dg-warning "writing 310 bytes" } */
+  T2 ("%*.*f", 311, 0);     /* { dg-warning "writing 311 bytes" } */
+  T2 ("%*.*f", 312, 312);   /* { dg-warning "between 314 and 623 bytes" } */
+  T2 ("%*.*f", 312, 313);   /* { dg-warning "between 315 and 624 bytes" } */
+
+  T1 ("%*.f", w);           /* { dg-warning "writing 1 or more bytes" } */
+  T1 ("%*.0f", w);          /* { dg-warning "writing 1 or more bytes" } */
+  T1 ("%*.1f", w);          /* { dg-warning "writing 3 or more bytes" } */
+  T1 ("%*.2f", w);          /* { dg-warning "writing 4 or more bytes" } */
+
+  T1 ("%.*f",  p);          /* { dg-warning "writing 1 or more bytes" } */
+  T1 ("%1.*f", p);          /* { dg-warning "writing 1 or more bytes" } */
+  T1 ("%2.*f", p);          /* { dg-warning "writing 2 or more bytes" } */
+  T1 ("%3.*f", p);          /* { dg-warning "writing 3 or more bytes" } */
+
+  T2 ("%*.*f", w, p);       /* { dg-warning "writing 1 or more bytes" } */
+  T2 ("%*.*f", w, p);       /* { dg-warning "writing 1 or more bytes" } */
+  T2 ("%*.*f", w, p);       /* { dg-warning "writing 1 or more bytes" } */
+}
+
+/* Exercise %g.  The expected output is the lesser of %e and %f.  */
+void test_g (double x)
+{
+  T1 ("%.*g", 0);           /* { dg-warning "between 1 and 7 bytes" } */
+  T1 ("%.*g", 1);           /* { dg-warning "between 1 and 7 bytes" } */
+  T1 ("%.*g", 2);           /* { dg-warning "between 1 and 9 bytes" } */
+  T1 ("%.*g", 99);          /* { dg-warning "between 1 and 106 bytes" } */
+  T1 ("%.*g", 199);         /* { dg-warning "between 1 and 206 bytes" } */
+  T1 ("%.*g", 1099);        /* { dg-warning "between 1 and 310 bytes" } */
+
+  T2 ("%*.*g", 0, 0);       /* { dg-warning "between 1 and 7 bytes" } */
+  T2 ("%*.*g", 1, 0);       /* { dg-warning "between 1 and 7 bytes" } */
+  T2 ("%*.*g", 2, 0);       /* { dg-warning "between 2 and 7 bytes" } */
+  T2 ("%*.*g", 3, 0);       /* { dg-warning "between 3 and 7 bytes" } */
+  T2 ("%*.*g", 7, 0);       /* { dg-warning "writing 7 bytes" } */
+  T2 ("%*.*g", 310, 0);     /* { dg-warning "writing 310 bytes" } */
+  T2 ("%*.*g", 311, 0);     /* { dg-warning "writing 311 bytes" } */
+  T2 ("%*.*g", 312, 312);   /* { dg-warning "writing 312 bytes" } */
+  T2 ("%*.*g", 312, 313);   /* { dg-warning "writing 312 bytes" } */
+  T2 ("%*.*g", 333, 999);   /* { dg-warning "writing 333 bytes" } */
+}
+
+/* Exercise %a.  */
+void test_a_va (va_list va)
+{
+  T ("%.0a");       /* { dg-warning "between 6 and 10 bytes" } */
+  T ("%.1a");       /* { dg-warning "between 8 and 12 bytes" } */
+  T ("%.2a");       /* { dg-warning "between 9 and 13 bytes" } */
+  T ("%.99a");      /* { dg-warning "between 106 and 110 bytes" } */
+  T ("%.199a");     /* { dg-warning "between 206 and 210 bytes" } */
+  T ("%.1099a");    /* { dg-warning "between 1106 and 1110 bytes" } */
+
+  T ("%0.a");       /* { dg-warning "between 6 and 10 bytes" } */
+  T ("%1.a");       /* { dg-warning "between 6 and 10 bytes" } */
+  T ("%3.a");       /* { dg-warning "between 6 and 10 bytes" } */
+  T ("%6.a");       /* { dg-warning "between 6 and 10 bytes" } */
+  T ("%7.a");       /* { dg-warning "between 7 and 10 bytes" } */
+
+  T ("%*.a");       /* { dg-warning "writing 6 or more bytes" } */
+  T ("%*.0a");      /* { dg-warning "writing 6 or more bytes" } */
+  T ("%*.1a");      /* { dg-warning "writing 8 or more bytes" } */
+  T ("%*.2a");      /* { dg-warning "writing 9 or more bytes" } */
+
+  T ("%.*a");       /* { dg-warning "writing 6 or more bytes" } */
+  T ("%1.*a");      /* { dg-warning "writing 6 or more bytes" } */
+  T ("%2.*a");      /* { dg-warning "writing 6 or more bytes" } */
+  T ("%6.*a");      /* { dg-warning "writing 6 or more bytes" } */
+  T ("%9.*a");      /* { dg-warning "writing 9 or more bytes" } */
+
+  T ("%*.*a");      /* { dg-warning "writing 6 or more bytes" } */
+}
+
+/* Exercise %e.  */
+void test_e_va (va_list va)
+{
+  T ("%e");         /* { dg-warning "between 12 and 14 bytes" } */
+  T ("%+e");        /* { dg-warning "between 13 and 14 bytes" } */
+  T ("% e");        /* { dg-warning "between 13 and 14 bytes" } */
+  T ("%#e");        /* { dg-warning "between 12 and 14 bytes" } */
+  T ("%#+e");       /* { dg-warning "between 13 and 14 bytes" } */
+  T ("%# e");       /* { dg-warning "between 13 and 14 bytes" } */
+
+  T ("%.e");        /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%.0e");       /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%.1e");       /* { dg-warning "between 7 and 9 bytes" } */
+  T ("%.2e");       /* { dg-warning "between 8 and 10 bytes" } */
+  T ("%.99e");      /* { dg-warning "between 105 and 107 bytes" } */
+  T ("%.199e");     /* { dg-warning "between 205 and 207 bytes" } */
+  T ("%.1099e");    /* { dg-warning "between 1105 and 1107 bytes" } */
+
+  T ("%0.e");       /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%1.e");       /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%1.e");       /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%3.e");       /* { dg-warning "between 5 and 7 bytes" } */
+  T ("%6.e");       /* { dg-warning "between 6 and 7 bytes" } */
+  T ("%7.e");       /* { dg-warning "writing 7 bytes" } */
+
+  T ("%.*e");       /* { dg-warning "writing 5 or more bytes" } */
+  T ("%1.*e");      /* { dg-warning "writing 5 or more bytes" } */
+  T ("%6.*e");      /* { dg-warning "writing 6 or more bytes" } */
+  T ("%9.*e");      /* { dg-warning "writing 9 or more bytes" } */
+
+  T ("%*.*e");      /* { dg-warning "writing 5 or more bytes" } */
+}
+
+/* Exercise %f.  */
+void test_f_va (va_list va)
+{
+  T ("%f");         /* { dg-warning "between 8 and 317 bytes" } */
+  T ("%+f");        /* { dg-warning "between 9 and 317 bytes" } */
+  T ("% f");        /* { dg-warning "between 9 and 317 bytes" } */
+  T ("%#f");        /* { dg-warning "between 8 and 317 bytes" } */
+  T ("%+f");        /* { dg-warning "between 9 and 317 bytes" } */
+  T ("% f");        /* { dg-warning "between 9 and 317 bytes" } */
+  T ("%#+f");       /* { dg-warning "between 9 and 317 bytes" } */
+  T ("%# f");       /* { dg-warning "between 9 and 317 bytes" } */
+
+  T ("%.f");        /* { dg-warning "between 1 and 310 bytes" } */
+  T ("%.0f");       /* { dg-warning "between 1 and 310 bytes" } */
+  T ("%.1f");       /* { dg-warning "between 3 and 312 bytes" } */
+  T ("%.2f");       /* { dg-warning "between 4 and 313 bytes" } */
+  T ("%.99f");      /* { dg-warning "between 101 and 410 bytes" } */
+  T ("%.199f");     /* { dg-warning "between 201 and 510 bytes" } */
+  T ("%.1099f");    /* { dg-warning "between 1101 and 1410 bytes" } */
+
+  T ("%0.0f");      /* { dg-warning "between 1 and 310 bytes" } */
+  T ("%1.0f");      /* { dg-warning "between 1 and 310 bytes" } */
+  T ("%2.0f");      /* { dg-warning "between 2 and 310 bytes" } */
+  T ("%3.0f");      /* { dg-warning "between 3 and 310 bytes" } */
+  T ("%310.0f");    /* { dg-warning "writing 310 bytes" } */
+  T ("%311.0f");    /* { dg-warning "writing 311 bytes" } */
+  T ("%312.312f");  /* { dg-warning "between 314 and 623 bytes" } */
+  T ("%312.313f");  /* { dg-warning "between 315 and 624 bytes" } */
+
+  T ("%.*f");       /* { dg-warning "writing 1 or more bytes" } */
+  T ("%1.*f");      /* { dg-warning "writing 1 or more bytes" } */
+  T ("%3.*f");      /* { dg-warning "writing 3 or more bytes" } */
+
+  T ("%*.*f");      /* { dg-warning "writing 1 or more bytes" } */
+}
+
+/* Exercise %g.  The expected output is the lesser of %e and %f.  */
+void test_g_va (va_list va)
+{
+  T ("%g");         /* { dg-warning "between 1 and 13 bytes" } */
+  T ("%+g");        /* { dg-warning "between 2 and 13 bytes" } */
+  T ("% g");        /* { dg-warning "between 2 and 13 bytes" } */
+  T ("%#g");        /* { dg-warning "between 1 and 13 bytes" } */
+  T ("%#+g");       /* { dg-warning "between 2 and 13 bytes" } */
+  T ("%# g");       /* { dg-warning "between 2 and 13 bytes" } */
+
+  T ("%.g");        /* { dg-warning "between 1 and 7 bytes" } */
+  T ("%.0g");       /* { dg-warning "between 1 and 7 bytes" } */
+  T ("%.1g");       /* { dg-warning "between 1 and 7 bytes" } */
+  T ("%.2g");       /* { dg-warning "between 1 and 9 bytes" } */
+  T ("%.99g");      /* { dg-warning "between 1 and 106 bytes" } */
+  T ("%.199g");     /* { dg-warning "between 1 and 206 bytes" } */
+  T ("%.1099g");    /* { dg-warning "between 1 and 310 bytes" } */
+
+  T ("%0.0g");      /* { dg-warning "between 1 and 7 bytes" } */
+  T ("%1.0g");      /* { dg-warning "between 1 and 7 bytes" } */
+  T ("%2.0g");      /* { dg-warning "between 2 and 7 bytes" } */
+  T ("%3.0g");      /* { dg-warning "between 3 and 7 bytes" } */
+  T ("%7.0g");      /* { dg-warning "writing 7 bytes" } */
+  T ("%310.0g");    /* { dg-warning "writing 310 bytes" } */
+  T ("%311.0g");    /* { dg-warning "writing 311 bytes" } */
+  T ("%312.312g");  /* { dg-warning "writing 312 bytes" } */
+  T ("%312.313g");  /* { dg-warning "writing 312 bytes" } */
+  T ("%333.999g");  /* { dg-warning "writing 333 bytes" } */
+
+  T ("%.*g");       /* { dg-warning "writing 1 or more bytes" } */
+  T ("%1.*g");      /* { dg-warning "writing 1 or more bytes" } */
+  T ("%4.*g");      /* { dg-warning "writing 4 or more bytes" } */
+
+  T ("%*.*g");      /* { dg-warning "writing 1 or more bytes" } */
+}
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf.c b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf.c
index 916df79..b3d6128 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf.c
@@ -56,9 +56,12 @@ checkv (const char *func, int line, int res, int min, int max,
 
 	  fail = 1;
 	}
-      else
+      else if (min == max)
 	__builtin_printf ("PASS: %s:%i: \"%s\" result %i: \"%s\"\n",
 			  func, line, fmt, n, dst);
+      else
+	__builtin_printf ("PASS: %s:%i: \"%s\" result %i in [%i, %i]: \"%s\"\n",
+			  func, line, fmt, n, min, max, dst);
     }
 
   if (fail)
@@ -75,7 +78,7 @@ check (const char *func, int line, int res, int min, int max,
   __builtin_va_end (va);
 }
 
-char buffer[256];
+char buffer[4100];
 char* volatile dst = buffer;
 char* ptr = buffer;
 
@@ -368,6 +371,8 @@ test_a_double (double d)
   EQL ( 9, 10, "%.2a", 4.0);        /* 0x8.00p-1 */
   EQL (10, 11, "%.3a", 5.0);        /* 0xa.000p-1 */
 
+  EQL (11, 12, "%.*a", 4, 6.0);     /* 0xc.0000p-1 */
+  EQL (12, 13, "%.*a", 5, 7.0);     /* 0xe.00000p-1 */
 	                            /* d is in [ 0, -DBL_MAX ] */
   RNG ( 6, 10, 11, "%.0a", d);      /* 0x0p+0 ... -0x2p+1023 */
   RNG ( 6, 12, 13, "%.1a", d);      /* 0x0p+0 ... -0x2.0p+1023 */
@@ -385,7 +390,7 @@ test_a_long_double (void)
 }
 
 static void __attribute__ ((noinline, noclone))
-test_e_double (void)
+test_e_double (double d)
 {
   EQL (12, 13, "%e",  1.0e0);
   EQL (13, 14, "%e", -1.0e0);
@@ -407,10 +412,34 @@ test_e_double (void)
   EQL (12, 13, "%e",  1.0e-1);
   EQL (12, 13, "%e",  1.0e-12);
   EQL (13, 14, "%e",  1.0e-123);
+
+  RNG (12, 14, 15, "%e", d);
+  RNG ( 5,  7,  8, "%.e", d);
+  RNG ( 5,  7,  8, "%.0e", d);
+  RNG ( 7,  9, 10, "%.1e", d);
+  RNG ( 8, 10, 11, "%.2e", d);
+  RNG ( 9, 11, 12, "%.3e", d);
+  RNG (10, 12, 13, "%.4e", d);
+  RNG (11, 13, 14, "%.5e", d);
+  RNG (12, 14, 15, "%.6e", d);
+  RNG (13, 15, 16, "%.7e", d);
+
+  RNG (4006, 4008, 4009, "%.4000e", d);
+
+  RNG ( 5,  7,  8, "%.*e", 0, d);
+  RNG ( 7,  9, 10, "%.*e", 1, d);
+  RNG ( 8, 10, 11, "%.*e", 2, d);
+  RNG ( 9, 11, 12, "%.*e", 3, d);
+  RNG (10, 12, 13, "%.*e", 4, d);
+  RNG (11, 13, 14, "%.*e", 5, d);
+  RNG (12, 14, 15, "%.*e", 6, d);
+  RNG (13, 15, 16, "%.*e", 7, d);
+
+  RNG (4006, 4008, 4009, "%.*e", 4000, d);
 }
 
 static void __attribute__ ((noinline, noclone))
-test_e_long_double (void)
+test_e_long_double (long double d)
 {
   EQL (12, 13, "%Le",  1.0e0L);
   EQL (13, 14, "%Le", -1.0e0L);
@@ -443,10 +472,32 @@ test_e_long_double (void)
   EQL ( 8,  9, "%.1Le",   1.0e-111L);
   EQL (19, 20, "%.12Le",  1.0e-112L);
   EQL (20, 21, "%.13Le",  1.0e-113L);
+
+  /* The following correspond to the double results plus 1 for the upper
+     bound accounting for the four-digit exponent.  */
+  RNG (12, 15, 16, "%Le", d);    /* 0.000000e+00 ...  -1.189732e+4932 */
+  RNG ( 5,  8,  9, "%.Le", d);
+  RNG ( 5,  9, 10, "%.0Le", d);
+  RNG ( 7, 10, 11, "%.1Le", d);  /* 0.0e+00      ...  -1.2e+4932 */
+  RNG ( 8, 11, 12, "%.2Le", d);  /* 0.00e+00     ...  -1.19e+4932 */
+  RNG ( 9, 12, 13, "%.3Le", d);
+  RNG (10, 13, 14, "%.4Le", d);
+  RNG (11, 14, 15, "%.5Le", d);
+  RNG (12, 15, 16, "%.6Le", d);  /* same as plain "%Le" */
+  RNG (13, 16, 17, "%.7Le", d);  /* 0.0000000e+00 ... -1.1897315e+4932 */
+
+  RNG ( 5,  9, 10, "%.*Le", 0, d);
+  RNG ( 7, 10, 11, "%.*Le", 1, d);
+  RNG ( 8, 11, 12, "%.*Le", 2, d);
+  RNG ( 9, 12, 13, "%.*Le", 3, d);
+  RNG (10, 13, 14, "%.*Le", 4, d);
+  RNG (11, 14, 15, "%.*Le", 5, d);
+  RNG (12, 15, 16, "%.*Le", 6, d);
+  RNG (13, 16, 17, "%.*Le", 7, d);
 }
 
 static void __attribute__ ((noinline, noclone))
-test_f_double (void)
+test_f_double (double d)
 {
   EQL (  8,   9, "%f", 0.0e0);
   EQL (  8,   9, "%f", 0.1e0);
@@ -464,6 +515,8 @@ test_f_double (void)
   EQL (  8,   9, "%f", 1.0e-1);
   EQL (  8,   9, "%f", 1.0e-12);
   EQL (  8,   9, "%f", 1.0e-123);
+
+  RNG (  8, 317, 318, "%f", d);
 }
 
 static void __attribute__ ((noinline, noclone))
@@ -488,6 +541,87 @@ test_f_long_double (void)
 }
 
 static void __attribute__ ((noinline, noclone))
+test_g_double (double d)
+{
+  /* Numbers exactly representable in binary floating point.  */
+  EQL (  1,   2, "%g", 0.0);
+  EQL (  3,   4, "%g", 1.0 / 2);
+  EQL (  4,   5, "%g", 1.0 / 4);
+  EQL (  5,   6, "%g", 1.0 / 8);
+  EQL (  6,   7, "%g", 1.0 / 16);
+  EQL (  7,   8, "%g", 1.0 / 32);
+  EQL (  8,   9, "%g", 1.0 / 64);
+  EQL (  9,  10, "%g", 1.0 / 128);
+  EQL ( 10,  11, "%g", 1.0 / 256);
+  EQL ( 10,  11, "%g", 1.0 / 512);
+
+  /* Numbers that are not exactly representable.  */
+  RNG ( 3,  8,  9, "%g", 0.1);
+  RNG ( 4,  8,  9, "%g", 0.12);
+  RNG ( 5,  8,  9, "%g", 0.123);
+  RNG ( 6,  8,  9, "%g", 0.1234);
+  RNG ( 7,  8,  9, "%g", 0.12345);
+  RNG ( 8,  8,  9, "%g", 0.123456);
+
+  RNG ( 4,  7,  8, "%g", 0.123e+1);
+  EQL (     8,  9, "%g", 0.123e+12);
+  RNG ( 9, 12, 13, "%g", 0.123e+134);
+
+  RNG ( 1, 13, 14, "%g", d);
+  RNG ( 1,  7,  8, "%.g", d);
+  RNG ( 1,  7,  8, "%.0g", d);
+  RNG ( 1,  7,  8, "%.1g", d);
+  RNG ( 1,  9, 10, "%.2g", d);
+  RNG ( 1, 10, 11, "%.3g", d);
+  RNG ( 1, 11, 12, "%.4g", d);
+  RNG ( 1, 12, 13, "%.5g", d);
+  RNG ( 1, 13, 14, "%.6g", d);
+  RNG ( 1, 14, 15, "%.7g", d);
+  RNG ( 1, 15, 16, "%.8g", d);
+
+  RNG ( 1,310,311, "%.9999g", d);
+
+  RNG ( 1,  7,  8, "%.*g", 0, d);
+  RNG ( 1,  7,  8, "%.*g", 1, d);
+  RNG ( 1,  9, 10, "%.*g", 2, d);
+  RNG ( 1, 10, 11, "%.*g", 3, d);
+  RNG ( 1, 11, 12, "%.*g", 4, d);
+  RNG ( 1, 12, 13, "%.*g", 5, d);
+  RNG ( 1, 13, 14, "%.*g", 6, d);
+  RNG ( 1, 14, 15, "%.*g", 7, d);
+  RNG ( 1, 15, 16, "%.*g", 8, d);
+  RNG ( 1,310,311, "%.*g", 9999, d);
+}
+
+static void __attribute__ ((noinline, noclone))
+test_g_long_double (void)
+{
+  /* Numbers exactly representable in binary floating point.  */
+  EQL (  1,   2, "%Lg", 0.0L);
+  EQL (  3,   4, "%Lg", 1.0L / 2);
+  EQL (  4,   5, "%Lg", 1.0L / 4);
+  EQL (  5,   6, "%Lg", 1.0L / 8);
+  EQL (  6,   7, "%Lg", 1.0L / 16);
+  EQL (  7,   8, "%Lg", 1.0L / 32);
+  EQL (  8,   9, "%Lg", 1.0L / 64);
+  EQL (  9,  10, "%Lg", 1.0L / 128);
+  EQL ( 10,  11, "%Lg", 1.0L / 256);
+  EQL ( 10,  11, "%Lg", 1.0L / 512);
+
+  /* Numbers that are not exactly representable.  */
+  RNG ( 3,  8,  9, "%Lg", 0.1L);
+  RNG ( 4,  8,  9, "%Lg", 0.12L);
+  RNG ( 5,  8,  9, "%Lg", 0.123L);
+  RNG ( 6,  8,  9, "%Lg", 0.1234L);
+  RNG ( 7,  8,  9, "%Lg", 0.12345L);
+  RNG ( 8,  8,  9, "%Lg", 0.123456L);
+
+  RNG ( 4,  7,  8, "%Lg", 0.123e+1L);
+  EQL (     8,  9, "%Lg", 0.123e+12L);
+  RNG ( 9, 12, 13, "%Lg", 0.123e+134L);
+}
+
+static void __attribute__ ((noinline, noclone))
 test_s (int i)
 {
   EQL (  0,   1, "%s", "");
@@ -530,12 +664,14 @@ int main (void)
   test_x ('?', 0xdead, 0xdeadbeef);
 
   test_a_double (0.0);
-  test_e_double ();
-  test_f_double ();
+  test_e_double (0.0);
+  test_f_double (0.0);
+  test_g_double (0.0);
 
   test_a_long_double ();
-  test_e_long_double ();
+  test_e_long_double (0.0);
   test_f_long_double ();
+  test_g_long_double ();
 
   test_s (0);
 
