How to fix 'Could not locate executable on path: gnatmake'

[resander <kresander@yahoo.com>]

I installed (by doinstall) the latest version of free GNAT GPL from
Libre into directory /usr/gnat/bin. After install this contains:

ken@meijin-desktop:/usr/gnat/bin$ ls
addr2line  gdb        gnathtml.pl  gnatprep         gprof
c++        gdbserver  gnatkr       gnatstub         gps
cbrowser   gnat       gnatlink     gnatxref         gps_exe
cpp        gnatbind   gnatls       gprbuild         i686-pc-linux-gnu-c
++
dbimp      gnatcheck  gnatmake     gprbuild_debug   i686-pc-linux-gnu-g
++
g++        gnatchop   gnatmem      gprclean         i686-pc-linux-gnu-
gcc
gcc        gnatclean  gnatmetric   gprclean_debug   i686-pc-linux-gnu-
gcc-4.3.4
gccbug     gnatelim   gnatname     gprconfig        objdump
gcov       gnatfind   gnatpp       gprconfig_debug


I added /usr/gnat/bin to the (Ubuntu 10.04) bashrc startup script of
the user 'ken' from which I want to use GPS. The echo command

echo $PATH
/usr/gnat/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/
bin:/usr/games

issued after login to 'ken' shows that /usr/gnat/bin is on the path.

gnatmake works from the command line for a small test program main.adb
in adatestproj directory:

ken@meijin-desktop:/home$ ls
ken  kr  lost+found  meijin

ken@meijin-desktop:/home$ cd ken
ken@meijin-desktop:~$ ls
adatestproj Documents  Music Videos...

ken@meijin-desktop:~$ cd adatestproj
ken@meijin-desktop:~/adatestproj$ ls
main.adb main.gpr
ken@meijin-desktop:~/adatestproj$ gnatmake main.adb
gcc -c main.adb
gnatbind -x main.ali
gnatlink main.ali


but from GPS 'Could not locate executable on path: gnatmake' appears
when I request compile file from adaptestproj directory.

I cannot see what is wrong. Would be grateful for advice.