middle-end/97855 - avoid recursing into pp_printf

When diagnostic messages use pretty-printer formats like %D or %E
the pp_printf invocation can end up in tree pretty-printers which
then have to avoid using pp_printf themselves since this function
is not re-entrant.

The following removes all pp_printf uses from tree-pretty-print.c
fixing the observed malformed diagnostics.  It also poisons the
identifier so new uses are less likely to creep in.

2021-03-04  Richard Biener  <rguenther@suse.de>

	PR middle-end/97855
	* tree-pretty-print.c: Poison pp_printf.
	(dump_decl_name): Avoid use of pp_printf.
	(dump_block_node): Likewise.
	(dump_generic_node): Likewise.

1 files changed, 74 insertions, 21 deletions

diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index 986f75d..62899df 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -36,6 +36,11 @@ along with GCC; see the file COPYING3.  If not see
 #include "gimple.h"
 #include "fold-const.h"
 
+/* Routines in this file get invoked via the default tree printer
+   used by diagnostics and thus they are called from pp_printf which
+   isn't reentrant.  Avoid using pp_printf in this file.  */
+#pragma GCC poison pp_printf
+
 /* Disable warnings about quoting issues in the pp_xxx calls below
    that (intentionally) don't follow GCC diagnostic conventions.  */
 #if __GNUC__ >= 10
@@ -293,29 +298,41 @@ dump_decl_name (pretty_printer *pp, tree node, dump_flags_t flags)
   if ((flags & TDF_UID) || name == NULL_TREE)
     {
       if (TREE_CODE (node) == LABEL_DECL && LABEL_DECL_UID (node) != -1)
-	pp_printf (pp, "L%c%d", uid_sep, (int) LABEL_DECL_UID (node));
+	{
+	  pp_character (pp, 'L');
+	  pp_character (pp, uid_sep);
+	  pp_decimal_int (pp, (int) LABEL_DECL_UID (node));
+	}
       else if (TREE_CODE (node) == DEBUG_EXPR_DECL)
 	{
 	  if (flags & TDF_NOUID)
 	    pp_string (pp, "D#xxxx");
 	  else
-	    pp_printf (pp, "D#%i", DEBUG_TEMP_UID (node));
+	    {
+	      pp_string (pp, "D#");
+	      pp_decimal_int (pp, (int) DEBUG_TEMP_UID (node));
+	    }
 	}
       else
 	{
 	  char c = TREE_CODE (node) == CONST_DECL ? 'C' : 'D';
+	  pp_character (pp, c);
+	  pp_character (pp, uid_sep);
 	  if (flags & TDF_NOUID)
-	    pp_printf (pp, "%c.xxxx", c);
+	    pp_string (pp, "xxxx");
 	  else
-	    pp_printf (pp, "%c%c%u", c, uid_sep, DECL_UID (node));
+	    pp_scalar (pp, "%u", DECL_UID (node));
 	}
     }
   if ((flags & TDF_ALIAS) && DECL_PT_UID (node) != DECL_UID (node))
     {
       if (flags & TDF_NOUID)
-	pp_printf (pp, "ptD.xxxx");
+	pp_string (pp, "ptD.xxxx");
       else
-	pp_printf (pp, "ptD.%u", DECL_PT_UID (node));
+	{
+	  pp_string (pp, "ptD.");
+	  pp_scalar (pp, "%u", DECL_PT_UID (node));
+	}
     }
 }
 
@@ -1328,10 +1345,16 @@ dump_block_node (pretty_printer *pp, tree block, int spc, dump_flags_t flags)
 {
   tree t;
 
-  pp_printf (pp, "BLOCK #%d ", BLOCK_NUMBER (block));
+  pp_string (pp, "BLOCK #");
+  pp_decimal_int (pp, BLOCK_NUMBER (block));
+  pp_character (pp, ' ');
 
   if (flags & TDF_ADDRESS)
-    pp_printf (pp, "[%p] ", (void *) block);
+    {
+      pp_character (pp, '[');
+      pp_scalar (pp, "%p", (void *) block);
+      pp_string (pp, "] ");
+    }
 
   if (TREE_ASM_WRITTEN (block))
     pp_string (pp, "[written] ");
@@ -1650,7 +1673,11 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
   is_expr = EXPR_P (node);
 
   if (is_stmt && (flags & TDF_STMTADDR))
-    pp_printf (pp, "<&%p> ", (void *)node);
+    {
+      pp_string (pp, "<&");
+      pp_scalar (pp, "%p", (void *)node);
+      pp_string (pp, "> ");
+    }
 
   if ((flags & TDF_LINENO) && EXPR_HAS_LOCATION (node))
     dump_location (pp, EXPR_LOCATION (node));
@@ -1857,9 +1884,13 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
 	  if (TYPE_IDENTIFIER (node))
 	    dump_generic_node (pp, TYPE_NAME (node), spc, flags, false);
 	  else if (flags & TDF_NOUID)
-	    pp_printf (pp, "<Txxxx>");
+	    pp_string (pp, "<Txxxx>");
 	  else
-	    pp_printf (pp, "<T%x>", TYPE_UID (node));
+	    {
+	      pp_string (pp, "<T");
+	      pp_scalar (pp, "%x", TYPE_UID (node));
+	      pp_character (pp, '>');
+	    }
 
 	  pp_right_paren (pp);
 	  dump_function_declaration (pp, fnode, spc, flags);
@@ -2137,9 +2168,13 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
       else if (TYPE_NAME (node) && DECL_NAME (TYPE_NAME (node)))
 	dump_decl_name (pp, TYPE_NAME (node), flags);
       else if (flags & TDF_NOUID)
-	pp_printf (pp, "<Txxxx>");
+	pp_string (pp, "<Txxxx>");
       else
-	pp_printf (pp, "<T%x>", TYPE_UID (node));
+	{
+	  pp_string (pp, "<T");
+	  pp_scalar (pp, "%x", TYPE_UID (node));
+	  pp_character (pp, '>');
+	}
       dump_function_declaration (pp, node, spc, flags);
       break;
 
@@ -2154,9 +2189,16 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
       else if (LABEL_DECL_UID (node) != -1)
 	{
 	  if (flags & TDF_GIMPLE)
-	    pp_printf (pp, "L%d", (int) LABEL_DECL_UID (node));
+	    {
+	      pp_character (pp, 'L');
+	      pp_decimal_int (pp, (int) LABEL_DECL_UID (node));
+	    }
 	  else
-	    pp_printf (pp, "<L%d>", (int) LABEL_DECL_UID (node));
+	    {
+	      pp_string (pp, "<L");
+	      pp_decimal_int (pp, (int) LABEL_DECL_UID (node));
+	      pp_character (pp, '>');
+	    }
 	}
       else
 	{
@@ -2165,9 +2207,16 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
 	  else
 	    {
 	      if (flags & TDF_GIMPLE)
-		pp_printf (pp, "<D%u>", DECL_UID (node));
+		{
+		  pp_character (pp, 'D');
+		  pp_scalar (pp, "%u", DECL_UID (node));
+		}
 	      else
-		pp_printf (pp, "<D.%u>", DECL_UID (node));
+		{
+		  pp_string (pp, "<D.");
+		  pp_scalar (pp, "%u", DECL_UID (node));
+		  pp_character (pp, '>');
+		}
 	    }
 	}
       break;
@@ -3021,9 +3070,12 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
 	  pp_string (pp, ", ivdep");
 	  break;
 	case annot_expr_unroll_kind:
-	  pp_printf (pp, ", unroll %d",
-		     (int) TREE_INT_CST_LOW (TREE_OPERAND (node, 2)));
-	  break;
+	  {
+	    pp_string (pp, ", unroll ");
+	    pp_decimal_int (pp,
+			    (int) TREE_INT_CST_LOW (TREE_OPERAND (node, 2)));
+	    break;
+	  }
 	case annot_expr_no_vector_kind:
 	  pp_string (pp, ", no-vector");
 	  break;
@@ -3205,7 +3257,8 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
       dump_generic_node (pp, CHREC_LEFT (node), spc, flags, false);
       pp_string (pp, ", +, ");
       dump_generic_node (pp, CHREC_RIGHT (node), spc, flags, false);
-      pp_printf (pp, "}_%u", CHREC_VARIABLE (node));
+      pp_string (pp, "}_");
+      pp_scalar (pp, "%u", CHREC_VARIABLE (node));
       is_stmt = false;
       break;