Intel® Fortran Compiler for Linux* and Mac OS X*

Quad precision (real*16) accuracy problems


The quadruple precision available in ifort-9.0 is supposed to
be a IEEE-style floating point format with 113 bits of accuracy, right?

It seems that sometimes it doesn't seem to have the full 113 bits
of accuracy; the following program finds the smallest i such that
fl(2^i + 1) - 2^i != 1, but if fails around i = 81 already.

Is there a but in the quad precision emulation somewhere?

problem using -ipo linking with ICC object files

I've been using ICC to build seti@home for a while and think I know -ipo with ICC well.

Now I'm building scilab (available with Intel Fortran and C++ compilers. I can build it with -ip flag with IFORT/ICC, but when I change -ip flag(s) to -ipo, linking fails with

ld: /tmp/ipo_ifortUx2MaC.o: No such file: No such file or directory

error. Does it mean IPO with mixed environment of IFORT/ICC is impossible? My options for ICC/IFORT are almost the same

Linspire 5.0 Installation

Good morning,

I am new to the Linux world and have begun using Linspire 5.0. I'd like to try the Intel FORTRAN compiler on that system, but I cannot get it to install. I can run the script, but it won't let me choose any of the options. If I close that session and try again, the OS tells me there is another instance of the script already running. Has anyone tried to install and usethis compiler on Linspire?


Internal compiler error

Hi There
I am tring to compile wrf using intel fortran compiler v9.0 and it is crushing in the same time i have no problems to compile the wrf using pgi fortran compiler any help is wellcome

env settings:
source /opt/intel/fc/9.0/bin/
source /opt/intel/idb/9.0/bin/

export FC=ifort
export FFLAGS="-g -O2 -mp -recursive"
export CPPFLAGS="-DpgiFortran"
export CC=gcc
export F90=ifort
export CXX=g++
export F90FLAGS="-g -O2 -mp -recursive"
export CXXFLAGS="-g -02"

idb - help to understand what is going on?


I confess that I am a newbie as far as idb goes but since I cannot find my mistake and wonder whether someone out there could shed some light.

My program works for several different scenarios, but there is one that a segmentation fault comes out.

idb Trispec_sim

Intel Debugger for IA-32 -based Applications, Version 9.0-16, Build 20051121


object file name: Trispec_sim

Reading symbolic information from /home/eduardo/Hinich_2006/code_Trispec_sim/Trispec_sim...WARNING: unable to determine length of string variable.

undefined symbol: _intel_fast_memtest

wow not having a good week with fortran and it's only Tuesday!

Just updated my fortran compilers to l_fc_c_9.0.031 off the website and now when I try to run any code that it has compiled, or any code that was already compiled by the lasst version, I get the error

undefined symbol: _intel_fast_memtest

Rather suggestive that I've broken the libraries... I've tried reinstalling. Any suggestions?


ifcSeedRead and ifcSeedWrite for intel fortrean 9.0 compiler


I have donwloaded and installed fortran and C== compilers 9.0 for linux. Before I run version 7.0 and 8.0. When trying to recompile my programs ifort link is complaining of undefined ifcSeedRead and Write. I have checked the doc dir but I didn't find any fortran files there!

Isn't ifcSeedRead support anymore?

Many thanks


deallocation error

I've got some code in which I used derived type array pointers. At the end I deallocate them and get the following message,

*** glibc detected *** double free or corruption (top): 0x08249b38 ***
forrtl: error (76): IOT trap signal

Now I'm assuming this means that the array is not allocated already but I was wondering why I get this error message rather than the usual "array not allocated" message from the fortran run time?

Also, does anyone have any hints on debugging these types of errors?


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