We investigate the
XY spin-glass model in two and three dimensions using the domain-wall renormalization-group method. The results for systems of linear sizes up to
L=12 (2D) and
L=8 (3D) strongly suggest that the lower critical dimension for spin-glass ordering may be ${d}_{\mathrm{c}}\ensuremath{\approx}3$, rather than 4 as is commonly believed. Our 3D data favor the scenario of a low but finite spin-glass ordering temperature below the chiral transition, but they are also compatible with the system being at or slightly below its lower critical dimension.