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Improved constant arithmetic: had several bugs

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This commit is contained in:
ceriel
1993-03-18 13:24:20 +00:00
parent a2bf695f83
commit a2cb61e0f0
11 changed files with 212 additions and 66 deletions
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33
lang/cem/cpp.ansi/LLlex.c
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@@ -259,7 +259,10 @@ garbage:
}
case STNUM: /* a numeric constant */
{ /* it may only be an integer constant */
register int base = 10, val = 0, vch;
register int base = 10, vch;
register arith val = 0;
int ovfl = 0;
arith ubound = ~(1<<(sizeof(arith)*8-1))/(base/2);
/* Since the preprocessor only knows integers and has
* nothing to do with ellipsis we just return when the
@@ -279,11 +282,35 @@ garbage:
}
while ((vch = val_in_base(ch, base)) >= 0) {
val = val * base + vch; /* overflow? nah */
if (val < 0 || val > ubound) ovfl++;
val *= base;
if (val < 0 && val + vch >= 0) ovfl++;
val += vch;
ch = GetChar();
}
while (ch == 'l' || ch == 'L' || ch == 'u' || ch == 'U')
ptok->tk_unsigned = 0;
if (ch == 'u' || ch == 'U') {
ptok->tk_unsigned = 1;
ch = GetChar();
if (ch == 'l' || ch == 'L') {
ch = GetChar();
}
}
else if (ch == 'l' || ch == 'L') {
ch = GetChar();
if (ch == 'u' || ch == 'U') {
ptok->tk_unsigned = 1;
ch = GetChar();
}
}
if (ovfl) {
warning("overflow in constant");
ptok->tk_unsigned = 1;
}
else if (val < 0) {
/* give warning??? */
ptok->tk_unsigned = 1;
}
UnGetChar();
ptok->tk_val = val;
return ptok->tk_symb = INTEGER;