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digitalmars.D.bugs - [Issue 1016] New: CTFE fails with recursive functions

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1016

           Summary: CTFE fails with recursive functions
           Product: D
           Version: 1.007
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: clugdbug yahoo.com.au


This seems to be a tail recursion problem? Calling the function recursively
(while ignoring the result) seems to clobber the local value of the variable.
I'm not sure if line (3) is the same bug or not; there seems to be a morass of
related bugs in the CTFE stuff.

-----------------

int exprLength(char [] s)
{
    int numParens=0;
    for (int i=0; i<s.length; ++i) {
        if (s[i]=='(') { numParens++; }
        if (s[i]==')') { numParens--; }
        if (numParens == 0) { return i; }
    }
}

char [] makePostfix(char [] operations)
{
    if (operations.length<2) return "x";
    int x = exprLength(operations);
    char [] first="bad";
    if (x>0) {
        first = "ok";
        char [] ignore = makePostfix(operations[1..x]); // This makes (2) fail.
    }
    return first;
}


void main()
{
    char [] q = makePostfix("(a+b)*c");
    assert(q=="ok"); // (1) PASSES
    const char [] q2 = makePostfix("(a+b)*c");
    static assert(q2=="ok");  // (2) FAILS
   static assert(makePostfix("(a+b)*c")=="ok"); // (3) not evaluatable at
compile time
}


--
Mar 02 2007
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1016


thomas-dloop kuehne.cn changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         OS/Version|Windows                     |All





Added to DStress as
http://dstress.kuehne.cn/compile/c/const_43_A.d
http://dstress.kuehne.cn/compile/c/const_43_B.d
http://dstress.kuehne.cn/compile/c/const_43_C.d
http://dstress.kuehne.cn/compile/c/const_43_D.d


--
Mar 08 2007
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1016


thomas-dloop kuehne.cn changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED





Fixed in DMD-1.009


--
Mar 11 2007