Following pdf in the URL causes a crash in poppler due to the delete/free being called for an uninitialized pointer.  Verified on poppler 0.8.1 / 0.8.2, versions 0.6.x do not seem to have affected code.

Problem is in the AnnotQuadrilaterals::AnnotQuadrilaterals in Annot.cc.  Whenever the code detects some problem with correctness of the data read from the PDF file, it attempts to free previously allocated members of quads[] and quads itself.  However, for-loop freeing previously allocated members of quads[] seems to be off-by-one, trying to free an uninitialized pointer.

In the loop 'while (i < (quadsLength) && correct)' i is incremented regardless of whether correct or incorrect data were read from the file.  If correct is gFalse after leaving the loop, i is number of initialized quads members + 1 (not number of initialized quads members as code assumes).

Possible solutions:
- use j < i - 1 in the for loop freeing quads[]
- break while loop when incorrect value is detected, skipping i++