Changes in pari 2.15.3:

• rare infinite loop in idealtwoelt [#2437]
• nfisisom(16*x^4+1,16*x^4+1) -> error [#2432]
• forprimestep(p=a,b,q,) overflow when a > primelimit]#2439]
• lfun([bnrinit(bnfinit(y^2+1),12),[[2,0],[6,0]]],2) -> error
• lfunthetacost(polcyclo(43)): silent overflow
• ellcard(ellinit([1,1]*ffgen([41,16])))-> impossible inverse [#2441]
• wrong result (missing content) in idealred(nf, [id, elt])
• det(integer matrix) -> inconsistent exact division [#2445]
• fft([],[]) -> SEGV, fft([1],[1]) -> SEGV
• nfrootsof1(x^0) -> oo-loop
• hgmalpha did not check its input
• hyperellchangecurve([],[]) -> SEGV
• hyperellchangecurve(x^0,[1,matid(2),0]) -> SEGV
• rnfeltnorm(x,x) -> SEGV
• polylogmult(1,[],-1) -> SEGV
• ellheight(non-integral E) -> crash [#2448]
• content(1,y) -> pol_1(y) instead of t_INT 1
• s=taylor(1/((x-1)*(y-1)),x); taylor(s,y) -> invalid object [#2452]
• avoid crashing when sumnumsidi diverges (0 bits of accuracy) [#2454]