Compilation error of Chain.f on IBM P690 machine

[jameschen]

Dear VTSTcode users,
I downloaded the latest vtstcode.tar.gz to our IBM P690 machine (AIX with xlf). I have compiled and ran the standard VASP 4.6 on this machine without any problem.
I'd like to apply VTSTcode to my research. Therefore,
I compiled the vasp.4.lib code at first. The makefile was the default makefile for RS6000 in vasp.4.lib folder. It works without any problem. Then, I just followed the building guidelines of vtstcode: copied the source codes of vtstcode into the vasp.4.6 folder and add the following objects, "tet.o hamil.o steep.o dimer.o dynmat.o neb.o lanczos.o \
sd.o cg.o qm.o lbfgs.o bfgs.o fire.o opt.o \ ", into the Makefile, which is the default makefile for rs6000 in vasp.4.6 folder.

I encountered the error messages listed in the following:
xlf90 -O4 -qarch=auto -c chain.f
"chain.f", line 147.13: 1511-025 (S) Logical expressions must only be compared using EQV and NEQV operators.
"chain.f", line 147.28: 1511-025 (S) Logical expressions must only be compared using EQV and NEQV operators.
** chain === End of Compilation 1 ===
1501-511 Compilation failed for file chain.f.
make: 1254-004 The error code from the last command is 1.


Could anyone give me some guidelines for tackling this problem?
Thank you very much.
Sincerely,
James

[graeme]

Thanks for pointing out this problem. The code has been updated to avoid the statement that xlf is complaining about.

[jameschen]

[quote="graeme"]Thanks for pointing out this problem. The code has been updated to avoid the statement that xlf is complaining about.[/quote]
I appreciate your help and great effort.
I have already compiled vtstcode in IBM P690 machine successfully.