https://community.intel.com/t5/Software-Archive/Re-debug-vs-release/m-p/986613#M27284 The following have helpt me to elliminate differences between debug and release results, and may help you too: <BR />1- Use IMPLICIT NONE and declare all of your variables; <BR />2- Initialize all variables, especially arrays; <BR />3- Do not mix up REAL with REAL*8 and INTEGER in the same calculation; <BR />4- Do use D (for double precision) with your constants if you declare the variables as double precision (e.g. X=0D0, Y=1D0 rather than X=0, Y=1 -- if X and Y are REAL*8); <BR />5- Be carefull with logical results of such comparisons as IF(X-Y == 0D0) THEN... This may behave different for debug vs release if X and Y are calculated values; <BR />6- Read Dave Eklunds 'The Perils of Real Numbers' in CVF Newsletter issues 8, 9 and 10. <BR /> <BR />Regards, <BR />Sabalan. Tue, 19 Mar 2002 20:49:39 GMT sabalan 2002-03-19T20:49:39Z https://community.intel.com/t5/Software-Archive/Re-debug-vs-release/m-p/986613#M27284 The following have helpt me to elliminate differences between debug and release results, and may help you too: <BR />1- Use IMPLICIT NONE and declare all of your variables; <BR />2- Initialize all variables, especially arrays; <BR />3- Do not mix up REAL with REAL*8 and INTEGER in the same calculation; <BR />4- Do use D (for double precision) with your constants if you declare the variables as double precision (e.g. X=0D0, Y=1D0 rather than X=0, Y=1 -- if X and Y are REAL*8); <BR />5- Be carefull with logical results of such comparisons as IF(X-Y == 0D0) THEN... This may behave different for debug vs release if X and Y are calculated values; <BR />6- Read Dave Eklunds 'The Perils of Real Numbers' in CVF Newsletter issues 8, 9 and 10. <BR /> <BR />Regards, <BR />Sabalan. Tue, 19 Mar 2002 20:49:39 GMT https://community.intel.com/t5/Software-Archive/Re-debug-vs-release/m-p/986613#M27284 sabalan 2002-03-19T20:49:39Z