In ecc-eddsa.c line 728 :
https://dev.gnupg.org/source/libgcrypt/browse/master/cipher/ecc-eddsa.c;0f2c6ce2c9504c6df435463243edaa669e57b109$763

there is potential memory leak because h, s and ctx and points are allocated and not freed on error return if b!=256/8