PR fortran/95828 - Buffer overflows with SELECT RANK

With SELECT RANK, name mangling results in long internal symbols that
overflows internal buffers.  Fix that.

gcc/fortran/
	PR fortran/95828
	* match.c (select_rank_set_tmp): Enlarge internal buffer used in
	generating a mangled name.
	* resolve.c (resolve_select_rank): Likewise.

(cherry picked from commit 77d455ee81ec3a23f8b20259a31ab963716f8e82)

gcc/fortran/match.c

@@ -6496,7 +6496,7 @@ static void
 select_rank_set_tmp (gfc_typespec *ts, int *case_value)
 {
   char name[2 * GFC_MAX_SYMBOL_LEN];
-  char tname[GFC_MAX_SYMBOL_LEN];
+  char tname[GFC_MAX_SYMBOL_LEN + 7];
   gfc_symtree *tmp;
   gfc_symbol *selector = select_type_stack->selector;
   gfc_symbol *sym;

gcc/fortran/resolve.c

@@ -9638,7 +9638,7 @@ resolve_select_rank (gfc_code *code, gfc_namespace *old_ns)
   gfc_namespace *ns;
   gfc_code *body, *new_st, *tail;
   gfc_case *c;
-  char tname[GFC_MAX_SYMBOL_LEN];
+  char tname[GFC_MAX_SYMBOL_LEN + 7];
   char name[2 * GFC_MAX_SYMBOL_LEN];
   gfc_symtree *st;
   gfc_expr *selector_expr = NULL;

gcc/testsuite/gfortran.dg/pr95828.f90

+! { dg-do compile }
+! { dg-options "-fsecond-underscore" }
+! PR fortran/95828 - ICE in resolve_select_rank, at fortran/resolve.c:9774
+
+module m2345678901234567890123456789012345678901234567890123456789_123
+  type t2345678901234567890123456789012345678901234567890123456789_123
+  end type
+contains
+  subroutine s2345678901234567890123456789012345678901234567890123456789_123 &
+            (x2345678901234567890123456789012345678901234567890123456789_123)
+    type    (t2345678901234567890123456789012345678901234567890123456789_123) :: &
+             x2345678901234567890123456789012345678901234567890123456789_123(..)
+
+    select rank (y2345678901234567890123456789012345678901234567890123456789_123 &
+              => x2345678901234567890123456789012345678901234567890123456789_123)
+    rank (2)
+    rank (3)
+    rank default
+    end select
+  end
+end