1 /* Parse C expressions for CCCP.
2 Copyright (C) 1987, 92, 94, 95, 97, 98, 1999, 2000 Free Software Foundation.
4 This program is free software; you can redistribute it and/or modify it
5 under the terms of the GNU General Public License as published by the
6 Free Software Foundation; either version 2, or (at your option) any
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, 59 Temple Place - Suite 330,
17 Boston, MA 02111-1307, USA.
19 In other words, you are welcome to use, share and improve this program.
20 You are forbidden to forbid anyone else to use, share and improve
21 what you give them. Help stamp out software-hoarding!
23 Written by Per Bothner 1994. */
25 /* Parse a C expression from text in a string */
31 #ifdef MULTIBYTE_CHARS
35 #ifndef CHAR_TYPE_SIZE
36 #define CHAR_TYPE_SIZE BITS_PER_UNIT
40 #define INT_TYPE_SIZE BITS_PER_WORD
43 #ifndef LONG_TYPE_SIZE
44 #define LONG_TYPE_SIZE BITS_PER_WORD
47 #ifndef WCHAR_TYPE_SIZE
48 #define WCHAR_TYPE_SIZE INT_TYPE_SIZE
51 #ifndef MAX_CHAR_TYPE_SIZE
52 #define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE
55 #ifndef MAX_INT_TYPE_SIZE
56 #define MAX_INT_TYPE_SIZE INT_TYPE_SIZE
59 #ifndef MAX_LONG_TYPE_SIZE
60 #define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE
63 #ifndef MAX_WCHAR_TYPE_SIZE
64 #define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE
67 #define MAX_CHAR_TYPE_MASK (MAX_CHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
68 ? (~ (~ (HOST_WIDEST_INT) 0 << MAX_CHAR_TYPE_SIZE)) \
69 : ~ (HOST_WIDEST_INT) 0)
71 #define MAX_WCHAR_TYPE_MASK (MAX_WCHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
72 ? ~ (~ (HOST_WIDEST_INT) 0 << MAX_WCHAR_TYPE_SIZE) \
73 : ~ (HOST_WIDEST_INT) 0)
75 /* Yield nonzero if adding two numbers with A's and B's signs can yield a
76 number with SUM's sign, where A, B, and SUM are all C integers. */
77 #define possible_sum_sign(a, b, sum) ((((a) ^ (b)) | ~ ((a) ^ (sum))) < 0)
79 static void integer_overflow PARAMS ((cpp_reader *));
80 static HOST_WIDEST_INT left_shift PARAMS ((cpp_reader *, HOST_WIDEST_INT, int, unsigned HOST_WIDEST_INT));
81 static HOST_WIDEST_INT right_shift PARAMS ((cpp_reader *, HOST_WIDEST_INT, int, unsigned HOST_WIDEST_INT));
82 static struct operation parse_number PARAMS ((cpp_reader *, U_CHAR *, U_CHAR *));
83 static struct operation parse_charconst PARAMS ((cpp_reader *, U_CHAR *, U_CHAR *));
84 static struct operation parse_defined PARAMS ((cpp_reader *));
85 static struct operation cpp_lex PARAMS ((cpp_reader *, int));
86 extern HOST_WIDEST_INT cpp_parse_expr PARAMS ((cpp_reader *));
87 static HOST_WIDEST_INT cpp_parse_escape PARAMS ((cpp_reader *, U_CHAR **, HOST_WIDEST_INT));
102 #define LEFT_OPERAND_REQUIRED 1
103 #define RIGHT_OPERAND_REQUIRED 2
105 /* SKIP_OPERAND is set for '&&' '||' '?' and ':' when the
106 following operand should be short-circuited instead of evaluated. */
107 #define SKIP_OPERAND 8
108 /*#define UNSIGNEDP 16*/
112 char rprio; /* Priority of op (relative to it right operand). */
114 char unsignedp; /* true if value should be treated as unsigned */
115 HOST_WIDEST_INT value; /* The value logically "right" of op. */
118 /* Parse and convert an integer for #if. Accepts decimal, hex, or octal
119 with or without size suffixes. */
121 static struct operation
122 parse_number (pfile, start, end)
130 unsigned HOST_WIDEST_INT n = 0, nd, MAX_over_base;
133 int digit, largest_digit = 0;
140 if (end - start >= 3 && (p[1] == 'x' || p[1] == 'X'))
152 /* Some buggy compilers (e.g. MPW C) seem to need both casts. */
153 MAX_over_base = (((unsigned HOST_WIDEST_INT) -1)
154 / ((unsigned HOST_WIDEST_INT) base));
160 if (c >= '0' && c <= '9')
162 else if (base == 16 && c >= 'a' && c <= 'f') /* FIXME: assumes ASCII */
163 digit = c - 'a' + 10;
164 else if (base == 16 && c >= 'A' && c <= 'F')
165 digit = c - 'A' + 10;
168 /* It's a float since it contains a point. */
170 "floating point numbers are not allowed in #if expressions");
175 /* `l' means long, and `u' means unsigned. */
178 if (c == 'l' || c == 'L')
180 else if (c == 'u' || c == 'U')
184 /* Decrement p here so that the error for an invalid number
185 will be generated below in the case where this is the
186 last character in the buffer. */
194 /* Don't look for any more digits after the suffixes. */
198 if (largest_digit < digit)
199 largest_digit = digit;
200 nd = n * base + digit;
201 overflow |= MAX_over_base < n || nd < n;
207 cpp_error (pfile, "invalid number in #if expression");
210 else if (spec_long > (CPP_OPTIONS (pfile)->c89 ? 1 : 2))
212 cpp_error (pfile, "too many `l' suffixes in integer constant");
215 else if (op.unsignedp > 1)
217 cpp_error (pfile, "too many `u' suffixes in integer constant");
221 if (base <= largest_digit)
222 cpp_pedwarn (pfile, "integer constant contains digits beyond the radix");
225 cpp_pedwarn (pfile, "integer constant out of range");
227 /* If too big to be signed, consider it unsigned. */
228 else if ((HOST_WIDEST_INT) n < 0 && ! op.unsignedp)
232 "integer constant is so large that it is unsigned");
245 /* Parse and convert a character constant for #if. Understands backslash
246 escapes (\n, \031) and multibyte characters (if so configured). */
247 static struct operation
248 parse_charconst (pfile, start, end)
254 HOST_WIDEST_INT result = 0;
257 unsigned int width = MAX_CHAR_TYPE_SIZE, mask = MAX_CHAR_TYPE_MASK;
261 /* FIXME: Should use reentrant multibyte functions. */
262 #ifdef MULTIBYTE_CHARS
263 wchar_t c = (wchar_t)-1;
264 (void) mbtowc (NULL_PTR, NULL_PTR, 0);
272 width = MAX_WCHAR_TYPE_SIZE, mask = MAX_WCHAR_TYPE_MASK;
274 max_chars = MAX_LONG_TYPE_SIZE / width;
276 ++ptr; /* skip initial quote */
280 #ifndef MULTIBYTE_CHARS
283 ptr += mbtowc (&c, ptr, end - ptr);
285 if (c == '\'' || c == '\0')
289 /* Hopefully valid assumption: if mbtowc returns a backslash,
290 we are in initial shift state. No valid escape-sequence
291 character can take us out of initial shift state or begin
292 an unshifted multibyte char, so cpp_parse_escape doesn't
293 need to know about multibyte chars. */
295 c = cpp_parse_escape (pfile, &ptr, mask);
296 if (width < HOST_BITS_PER_INT
297 && (unsigned int) c >= (unsigned int)(1 << width))
298 cpp_pedwarn (pfile, "escape sequence out of range for character");
301 /* Merge character into result; ignore excess chars. */
302 if (++num_chars <= max_chars)
304 if (width < HOST_BITS_PER_INT)
305 result = (result << width) | (c & ((1 << width) - 1));
313 cpp_error (pfile, "empty character constant");
318 /* cpp_get_token has already emitted an error if !traditional. */
319 if (! CPP_TRADITIONAL (pfile))
320 cpp_error (pfile, "malformatted character constant");
323 else if (num_chars > max_chars)
325 cpp_error (pfile, "character constant too long");
328 else if (num_chars != 1 && ! CPP_TRADITIONAL (pfile))
329 cpp_warning (pfile, "multi-character character constant");
331 /* If char type is signed, sign-extend the constant. */
332 num_bits = num_chars * width;
334 if (cpp_defined (pfile, (const U_CHAR *)"__CHAR_UNSIGNED__",
335 sizeof ("__CHAR_UNSIGNED__")-1)
336 || ((result >> (num_bits - 1)) & 1) == 0)
337 op.value = result & ((unsigned HOST_WIDEST_INT) ~0
338 >> (HOST_BITS_PER_WIDEST_INT - num_bits));
340 op.value = result | ~((unsigned HOST_WIDEST_INT) ~0
341 >> (HOST_BITS_PER_WIDEST_INT - num_bits));
343 /* This is always a signed type. */
353 static struct operation
354 parse_defined (pfile)
359 enum cpp_token token;
361 long old_written = CPP_WRITTEN (pfile);
366 pfile->no_macro_expand++;
367 token = get_directive_token (pfile);
368 if (token == CPP_LPAREN)
371 CPP_SET_WRITTEN (pfile, old_written);
372 token = get_directive_token (pfile);
375 if (token != CPP_NAME)
378 tok = pfile->token_buffer + old_written;
379 len = CPP_PWRITTEN (pfile) - tok;
380 op.value = cpp_defined (pfile, tok, len);
384 if (get_directive_token (pfile) != CPP_RPAREN)
387 CPP_SET_WRITTEN (pfile, old_written);
388 pfile->no_macro_expand--;
392 CPP_SET_WRITTEN (pfile, old_written);
393 pfile->no_macro_expand--;
394 cpp_error (pfile, "`defined' without an identifier");
402 const char *operator;
406 static struct token tokentab2[] = {
420 /* Read one token. */
422 static struct operation
423 cpp_lex (pfile, skip_evaluation)
427 struct token *toktab;
428 enum cpp_token token;
430 U_CHAR *tok_start, *tok_end;
433 old_written = CPP_WRITTEN (pfile);
434 token = get_directive_token (pfile);
436 tok_start = pfile->token_buffer + old_written;
437 tok_end = CPP_PWRITTEN (pfile);
438 CPP_SET_WRITTEN (pfile, old_written);
441 case CPP_EOF: /* Should not happen ... */
446 return parse_number (pfile, tok_start, tok_end);
449 cpp_error (pfile, "string constants are not allowed in #if expressions");
455 return parse_charconst (pfile, tok_start, tok_end);
458 if (!strcmp (tok_start, "defined"))
459 return parse_defined (pfile);
465 if (CPP_WARN_UNDEF (pfile) && !skip_evaluation)
466 cpp_warning (pfile, "`%.*s' is not defined",
467 (int) (tok_end - tok_start), tok_start);
473 op.value = cpp_defined (pfile, tok_start, tok_end - tok_start);
477 /* See if it is a special token of length 2. */
478 if (tok_start + 2 == tok_end)
480 for (toktab = tokentab2; toktab->operator != NULL; toktab++)
481 if (tok_start[0] == toktab->operator[0]
482 && tok_start[1] == toktab->operator[1])
484 if (toktab->token == ERROR)
485 cpp_error (pfile, "`%s' not allowed in operand of `#if'",
487 op.op = toktab->token;
498 /* Parse a C escape sequence. STRING_PTR points to a variable
499 containing a pointer to the string to parse. That pointer
500 is updated past the characters we use. The value of the
501 escape sequence is returned.
503 A negative value means the sequence \ newline was seen,
504 which is supposed to be equivalent to nothing at all.
506 If \ is followed by a null character, we return a negative
507 value and leave the string pointer pointing at the null character.
509 If \ is followed by 000, we return 0 and leave the string pointer
510 after the zeros. A value of 0 does not mean end of string. */
512 static HOST_WIDEST_INT
513 cpp_parse_escape (pfile, string_ptr, result_mask)
516 HOST_WIDEST_INT result_mask;
518 register int c = *(*string_ptr)++;
527 if (CPP_OPTIONS (pfile)->pedantic)
528 cpp_pedwarn (pfile, "non-ANSI-standard escape sequence, `\\%c'", c);
533 return TARGET_NEWLINE;
555 register HOST_WIDEST_INT i = c - '0';
556 register int count = 0;
559 c = *(*string_ptr)++;
560 if (c >= '0' && c <= '7')
561 i = (i << 3) + c - '0';
568 if (i != (i & result_mask))
571 cpp_pedwarn (pfile, "octal escape sequence out of range");
577 register unsigned HOST_WIDEST_INT i = 0, overflow = 0;
578 register int digits_found = 0, digit;
581 c = *(*string_ptr)++;
582 if (c >= '0' && c <= '9')
584 else if (c >= 'a' && c <= 'f')
585 digit = c - 'a' + 10;
586 else if (c >= 'A' && c <= 'F')
587 digit = c - 'A' + 10;
593 overflow |= i ^ (i << 4 >> 4);
594 i = (i << 4) + digit;
598 cpp_error (pfile, "\\x used with no following hex digits");
599 if (overflow | (i != (i & result_mask)))
602 cpp_pedwarn (pfile, "hex escape sequence out of range");
612 integer_overflow (pfile)
615 if (CPP_PEDANTIC (pfile))
616 cpp_pedwarn (pfile, "integer overflow in preprocessor expression");
619 static HOST_WIDEST_INT
620 left_shift (pfile, a, unsignedp, b)
624 unsigned HOST_WIDEST_INT b;
626 if (b >= HOST_BITS_PER_WIDEST_INT)
628 if (! unsignedp && a != 0)
629 integer_overflow (pfile);
633 return (unsigned HOST_WIDEST_INT) a << b;
636 HOST_WIDEST_INT l = a << b;
638 integer_overflow (pfile);
643 static HOST_WIDEST_INT
644 right_shift (pfile, a, unsignedp, b)
645 cpp_reader *pfile ATTRIBUTE_UNUSED;
648 unsigned HOST_WIDEST_INT b;
650 if (b >= HOST_BITS_PER_WIDEST_INT)
651 return unsignedp ? 0 : a >> (HOST_BITS_PER_WIDEST_INT - 1);
653 return (unsigned HOST_WIDEST_INT) a >> b;
658 /* These priorities are all even, so we can handle associatively. */
659 #define PAREN_INNER_PRIO 0
661 #define COND_PRIO (COMMA_PRIO+2)
662 #define OROR_PRIO (COND_PRIO+2)
663 #define ANDAND_PRIO (OROR_PRIO+2)
664 #define OR_PRIO (ANDAND_PRIO+2)
665 #define XOR_PRIO (OR_PRIO+2)
666 #define AND_PRIO (XOR_PRIO+2)
667 #define EQUAL_PRIO (AND_PRIO+2)
668 #define LESS_PRIO (EQUAL_PRIO+2)
669 #define SHIFT_PRIO (LESS_PRIO+2)
670 #define PLUS_PRIO (SHIFT_PRIO+2)
671 #define MUL_PRIO (PLUS_PRIO+2)
672 #define UNARY_PRIO (MUL_PRIO+2)
673 #define PAREN_OUTER_PRIO (UNARY_PRIO+2)
675 #define COMPARE(OP) \
677 top->value = (unsigned1 || unsigned2) \
678 ? (unsigned HOST_WIDEST_INT) v1 OP (unsigned HOST_WIDEST_INT) v2 : (v1 OP v2)
680 /* Parse and evaluate a C expression, reading from PFILE.
681 Returns the value of the expression. */
684 cpp_parse_expr (pfile)
687 /* The implementation is an operator precedence parser,
688 i.e. a bottom-up parser, using a stack for not-yet-reduced tokens.
690 The stack base is 'stack', and the current stack pointer is 'top'.
691 There is a stack element for each operator (only),
692 and the most recently pushed operator is 'top->op'.
693 An operand (value) is stored in the 'value' field of the stack
694 element of the operator that precedes it.
695 In that case the 'flags' field has the HAVE_VALUE flag set. */
697 #define INIT_STACK_SIZE 20
698 struct operation init_stack[INIT_STACK_SIZE];
699 struct operation *stack = init_stack;
700 struct operation *limit = stack + INIT_STACK_SIZE;
701 register struct operation *top = stack;
702 int lprio, rprio = 0;
703 int skip_evaluation = 0;
713 op = cpp_lex (pfile, skip_evaluation);
715 /* See if the token is an operand, in which case go to set_value.
716 If the token is an operator, figure out its left and right
717 priorities, and then goto maybe_reduce. */
722 cpp_ice (pfile, "cpp_lex returns a NAME");
727 lprio = 0; goto maybe_reduce;
729 if (top->flags & HAVE_VALUE)
734 /* else fall through */
736 flags = RIGHT_OPERAND_REQUIRED;
737 rprio = UNARY_PRIO; lprio = rprio + 1; goto maybe_reduce;
738 case '*': case '/': case '%':
739 lprio = MUL_PRIO; goto binop;
740 case '<': case '>': case LEQ: case GEQ:
741 lprio = LESS_PRIO; goto binop;
742 case EQUAL: case NOTEQUAL:
743 lprio = EQUAL_PRIO; goto binop;
745 lprio = SHIFT_PRIO; goto binop;
746 case '&': lprio = AND_PRIO; goto binop;
747 case '^': lprio = XOR_PRIO; goto binop;
748 case '|': lprio = OR_PRIO; goto binop;
749 case ANDAND: lprio = ANDAND_PRIO; goto binop;
750 case OROR: lprio = OROR_PRIO; goto binop;
752 lprio = COMMA_PRIO; goto binop;
754 lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO;
757 lprio = PAREN_INNER_PRIO; rprio = PAREN_OUTER_PRIO;
760 lprio = COND_PRIO; rprio = COND_PRIO;
763 lprio = COND_PRIO + 1; rprio = COND_PRIO;
768 cpp_error (pfile, "invalid character in #if");
773 /* Push a value onto the stack. */
774 if (top->flags & HAVE_VALUE)
776 cpp_error (pfile, "syntax error in #if");
779 top->value = op.value;
780 top->unsignedp = op.unsignedp;
781 top->flags |= HAVE_VALUE;
785 flags = LEFT_OPERAND_REQUIRED|RIGHT_OPERAND_REQUIRED;
789 /* Push an operator, and check if we can reduce now. */
790 while (top->rprio > lprio)
792 HOST_WIDEST_INT v1 = top[-1].value, v2 = top[0].value;
793 int unsigned1 = top[-1].unsignedp, unsigned2 = top[0].unsignedp;
795 if ((top[1].flags & LEFT_OPERAND_REQUIRED)
796 && ! (top[0].flags & HAVE_VALUE))
798 cpp_error (pfile, "syntax error - missing left operand");
801 if ((top[1].flags & RIGHT_OPERAND_REQUIRED)
802 && ! (top[1].flags & HAVE_VALUE))
804 cpp_error (pfile, "syntax error - missing right operand");
807 /* top[0].value = (top[1].op)(v1, v2);*/
811 if (!(top->flags & HAVE_VALUE))
814 top->unsignedp = unsigned2;
815 top->flags |= HAVE_VALUE;
819 top->value = v1 + v2;
820 top->unsignedp = unsigned1 || unsigned2;
821 if (! top->unsignedp && ! skip_evaluation
822 && ! possible_sum_sign (v1, v2, top->value))
823 integer_overflow (pfile);
827 if (!(top->flags & HAVE_VALUE))
830 if (!skip_evaluation && (top->value & v2) < 0 && !unsigned2)
831 integer_overflow (pfile);
832 top->unsignedp = unsigned2;
833 top->flags |= HAVE_VALUE;
837 top->value = v1 - v2;
838 top->unsignedp = unsigned1 || unsigned2;
839 if (! top->unsignedp && ! skip_evaluation
840 && ! possible_sum_sign (top->value, v2, v1))
841 integer_overflow (pfile);
845 top->unsignedp = unsigned1 || unsigned2;
847 top->value = (unsigned HOST_WIDEST_INT) v1 * v2;
848 else if (!skip_evaluation)
850 top->value = v1 * v2;
852 && (top->value / v1 != v2
853 || (top->value & v1 & v2) < 0))
854 integer_overflow (pfile);
862 cpp_error (pfile, "division by zero in #if");
865 top->unsignedp = unsigned1 || unsigned2;
867 top->value = (unsigned HOST_WIDEST_INT) v1 / v2;
870 top->value = v1 / v2;
871 if ((top->value & v1 & v2) < 0)
872 integer_overflow (pfile);
880 cpp_error (pfile, "division by zero in #if");
883 top->unsignedp = unsigned1 || unsigned2;
885 top->value = (unsigned HOST_WIDEST_INT) v1 % v2;
887 top->value = v1 % v2;
890 if (top->flags & HAVE_VALUE)
892 cpp_error (pfile, "syntax error");
897 top->flags |= HAVE_VALUE;
900 if (top->flags & HAVE_VALUE)
902 cpp_error (pfile, "syntax error");
906 top->unsignedp = unsigned2;
907 top->flags |= HAVE_VALUE;
909 case '<': COMPARE(<); break;
910 case '>': COMPARE(>); break;
911 case LEQ: COMPARE(<=); break;
912 case GEQ: COMPARE(>=); break;
914 top->value = (v1 == v2);
918 top->value = (v1 != v2);
924 top->unsignedp = unsigned1;
925 if (v2 < 0 && ! unsigned2)
926 top->value = right_shift (pfile, v1, unsigned1, -v2);
928 top->value = left_shift (pfile, v1, unsigned1, v2);
933 top->unsignedp = unsigned1;
934 if (v2 < 0 && ! unsigned2)
935 top->value = left_shift (pfile, v1, unsigned1, -v2);
937 top->value = right_shift (pfile, v1, unsigned1, v2);
939 #define LOGICAL(OP) \
940 top->value = v1 OP v2;\
941 top->unsignedp = unsigned1 || unsigned2;
942 case '&': LOGICAL(&); break;
943 case '^': LOGICAL(^); break;
944 case '|': LOGICAL(|); break;
946 top->value = v1 && v2; top->unsignedp = 0;
947 if (!v1) skip_evaluation--;
950 top->value = v1 || v2; top->unsignedp = 0;
951 if (v1) skip_evaluation--;
954 if (CPP_PEDANTIC (pfile))
955 cpp_pedwarn (pfile, "comma operator in operand of `#if'");
957 top->unsignedp = unsigned2;
960 cpp_error (pfile, "syntax error in #if");
963 if (top[0].op != '?')
966 "syntax error ':' without preceding '?'");
969 else if (! (top[1].flags & HAVE_VALUE)
970 || !(top[-1].flags & HAVE_VALUE)
971 || !(top[0].flags & HAVE_VALUE))
973 cpp_error (pfile, "bad syntax for ?: operator");
979 if (top->value) skip_evaluation--;
980 top->value = top->value ? v1 : v2;
981 top->unsignedp = unsigned1 || unsigned2;
985 if ((top[1].flags & HAVE_VALUE)
986 || ! (top[0].flags & HAVE_VALUE)
988 || (top[-1].flags & HAVE_VALUE))
990 cpp_error (pfile, "mismatched parentheses in #if");
997 top->unsignedp = unsigned1;
998 top->flags |= HAVE_VALUE;
1002 if (ISGRAPH (top[1].op))
1003 cpp_error (pfile, "unimplemented operator '%c'\n", top[1].op);
1005 cpp_error (pfile, "unimplemented operator '\\%03o'\n",
1012 cpp_ice (pfile, "unbalanced stack in #if expression");
1013 if (stack != init_stack)
1019 /* Check for and handle stack overflow. */
1022 struct operation *new_stack;
1023 int old_size = (char *) limit - (char *) stack;
1024 int new_size = 2 * old_size;
1025 if (stack != init_stack)
1026 new_stack = (struct operation *) xrealloc (stack, new_size);
1029 new_stack = (struct operation *) xmalloc (new_size);
1030 bcopy ((char *) stack, (char *) new_stack, old_size);
1033 top = (struct operation *) ((char *) new_stack + old_size);
1034 limit = (struct operation *) ((char *) new_stack + new_size);
1040 if ((op.op == OROR && top[-1].value)
1041 || (op.op == ANDAND && !top[-1].value)
1042 || (op.op == '?' && !top[-1].value))
1046 else if (op.op == ':')
1048 if (top[-2].value) /* Was condition true? */
1055 if (stack != init_stack)