cppexp.c (cpp_lex): Do cpp_pop_buffer after CPP_POP so retried cpp_skip_hspace will...

* cppexp.c (cpp_lex):  Do cpp_pop_buffer after CPP_POP so retried
cpp_skip_hspace will actually work.
* cppexp.c (SKIP_OPERAND):  New macro.
(cpp_parse_expr):  Suppress evaluation and diagnostics in
unevaluated subexpressions.

From-SVN: r11034

diff --git a/gcc/cppexp.c b/gcc/cppexp.c
index 6b73ad34e4dce09d6edfc7af74662e1755a0f680..b830f9b71ac465097063c68482eca0f1959b5838 100644 (file)
--- a/gcc/cppexp.c
+++ b/gcc/cppexp.c
@@ -121,7 +121,10 @@ static long right_shift ();
 #define LEFT_OPERAND_REQUIRED 1
 #define RIGHT_OPERAND_REQUIRED 2
 #define HAVE_VALUE 4
-/*#define UNSIGNEDP 8*/
+/* SKIP_OPERAND is set for '&&' '||' '?' and ':' when the
+   following operand should be short-circuited instead of evaluated. */
+#define SKIP_OPERAND 8
+/*#define UNSIGNEDP 16*/
 
 #ifndef HOST_BITS_PER_WIDE_INT
 
@@ -308,15 +311,16 @@ cpp_reader *pfile;
   switch (token)
   {
     case CPP_EOF: /* Should not happen ... */
+    case CPP_VSPACE:
       op.op = 0;
       return op;
-    case CPP_VSPACE:
     case CPP_POP:
       if (CPP_BUFFER (pfile)->fname != NULL)
        {
          op.op = 0;
          return op;
        }
+      cpp_pop_buffer (pfile);
       goto retry;
     case CPP_HSPACE:   case CPP_COMMENT: 
       goto retry;
@@ -670,6 +674,7 @@ cpp_parse_expr (pfile)
   struct operation *limit = stack + INIT_STACK_SIZE;
   register struct operation *top = stack;
   int lprio, rprio;
+  int skip_evaluation = 0;
 
   top->rprio = 0;
   top->flags = 0;
@@ -782,13 +787,14 @@ cpp_parse_expr (pfile)
                {
                  top->value = v1 + v2;
                  top->unsignedp = unsigned1 || unsigned2;
-                 if (! top->unsignedp
+                 if (! top->unsignedp && ! skip_evaluation
                      && ! possible_sum_sign (v1, v2, top->value))
                    integer_overflow (pfile);
                }
              break;
            case '-':
-             if (!(top->flags & HAVE_VALUE))
+             if (skip_evaluation) ;    /* do nothing */
+             else if (!(top->flags & HAVE_VALUE))
                { /* Unary '-' */
                  top->value = - v2;
                  if ((top->value & v2) < 0 && ! unsigned2)
@@ -809,7 +815,7 @@ cpp_parse_expr (pfile)
              top->unsignedp = unsigned1 || unsigned2;
              if (top->unsignedp)
                top->value = (unsigned long) v1 * v2;
-             else
+             else if (!skip_evaluation)
                {
                  top->value = v1 * v2;
                  if (v1
@@ -819,6 +825,8 @@ cpp_parse_expr (pfile)
                }
              break;
            case '/':
+             if (skip_evaluation)
+               break;
              if (v2 == 0)
                {
                  cpp_error (pfile, "division by zero in #if");
@@ -835,6 +843,8 @@ cpp_parse_expr (pfile)
                }
              break;
            case '%':
+             if (skip_evaluation)
+               break;
              if (v2 == 0)
                {
                  cpp_error (pfile, "division by zero in #if");
@@ -879,6 +889,8 @@ cpp_parse_expr (pfile)
              top->unsignedp = 0;
              break;
            case LSH:
+             if (skip_evaluation)
+               break;
              top->unsignedp = unsigned1;
              if (v2 < 0 && ! unsigned2)
                top->value = right_shift (pfile, v1, unsigned1, -v2);
@@ -886,6 +898,8 @@ cpp_parse_expr (pfile)
                top->value = left_shift (pfile, v1, unsigned1, v2);
              break;
            case RSH:
+             if (skip_evaluation)
+               break;
              top->unsignedp = unsigned1;
              if (v2 < 0 && ! unsigned2)
                top->value = left_shift (pfile, v1, unsigned1, -v2);
@@ -899,9 +913,13 @@ cpp_parse_expr (pfile)
            case '^':  LOGICAL(^);  break;
            case '|':  LOGICAL(|);  break;
            case ANDAND:
-             top->value = v1 && v2;  top->unsignedp = 0;  break;
+             top->value = v1 && v2;  top->unsignedp = 0;
+             if (!v1) skip_evaluation--;
+             break;
            case OROR:
-             top->value = v1 || v2;  top->unsignedp = 0;  break;
+             top->value = v1 || v2;  top->unsignedp = 0;
+             if (v1) skip_evaluation--;
+             break;
            case ',':
              if (CPP_PEDANTIC (pfile))
                cpp_pedwarn (pfile, "comma operator in operand of `#if'");
@@ -928,6 +946,7 @@ cpp_parse_expr (pfile)
              else
                {
                  top--;
+                 if (top->value) skip_evaluation--;
                  top->value = top->value ? v1 : v2;
                  top->unsignedp = unsigned1 || unsigned2;
                }
@@ -988,6 +1007,19 @@ cpp_parse_expr (pfile)
       top->flags = flags;
       top->rprio = rprio;
       top->op = op.op;
+      if ((op.op == OROR && top[-1].value)
+         || (op.op == ANDAND && !top[-1].value)
+         || (op.op == '?' && !top[-1].value))
+       {
+         skip_evaluation++;
+       }
+      else if (op.op == ':')
+       {
+         if (top[-2].value) /* Was condition true? */
+           skip_evaluation++;
+         else
+           skip_evaluation--;
+       }
     }
  syntax_error:
   if (stack != init_stack)