I'm seeing this:
make[4]: Entering directory `/home/postgres/pgsql/src/interfaces/ecpg/ecpglib'
...
gcc -O1 -fno-strict-aliasing -g -Wall -Wmissing-prototypes -Wmissing-declarations -fpic -DFRONTEND
-I../../../../src/interfaces/ecpg/include-I../../../../src/interfaces/libpq -I../../../../src/port
-I../../../../src/include-D_XOPEN_SOURCE_EXTENDED -c -o descriptor.o descriptor.c
descriptor.c: In function `ECPGset_desc':
descriptor.c:460: warning: assignment from incompatible pointer type
descriptor.c:438: warning: unused variable `last_di'
...
Looks like that last patch needs a bit o' work yet ...
regards, tom lane