Hi, We have gcc 4.8.3 installed on AIX 6.1; the binaries were kindly provided by the maintainter of this site: http://www.perzl.org/aix/index.php?n=Main.Gcc. Been trying to install/compile different R and Python packages, and I've been running into issues where multiple included header files contain the same symbols. An example could be found here https://github.com/Rdatatable/data.table/issues/1351, where we ultimately fixed the compilation error by changing the symbol names. Trying to compile numpy and other packages, and am also getting similar errors. When googling 'gcc aix previous declaration conflicting types', I see that many packages run into this problem. My question is why does this happen only in AIX? Is there any way to fix this? My guess is that GCC on other OS takes the symbol from the first header it encounters for the particular file, and ignores the rest. Can one specify this behavior in AIX as well? I'm pasting some sample error messages that I'm seeing while compiling numpy. Hope this would lead me to a solution. Thanks! In file included from /sas/data04/opt/include/python3.5m/Python.h:8:0, from numpy/core/src/umath/test_rational.c.src:6: /sas/data04/opt/include/python3.5m/pyconfig.h:1455:0: warning: "_XOPEN_SOURCE" redefined [enabled by default] #define _XOPEN_SOURCE 700 ^ In file included from /opt/freeware/lib/gcc/powerpc-ibm-aix6.1.0.0/4.8.3/include-fixed/math.h:51:0, from numpy/core/src/umath/test_rational.c.src:5: /usr/include/standards.h:152:0: note: this is the location of the previous definition #define _XOPEN_SOURCE 600 ^ In file included from /sas/data04/opt/include/python3.5m/Python.h:25:0, from numpy/core/src/umath/test_rational.c.src:6: /opt/freeware/lib/gcc/powerpc-ibm-aix6.1.0.0/4.8.3/include-fixed/stdio.h:512:12: error: conflicting types for 'fgetpos64' extern int fgetpos64(FILE *, fpos64_t *); ^ In file included from /sas/data04/opt/include/python3.5m/Python.h:25:0, from numpy/core/src/umath/test_rational.c.src:6: /opt/freeware/lib/gcc/powerpc-ibm-aix6.1.0.0/4.8.3/include-fixed/stdio.h:311:12: note: previous declaration of 'fgetpos64' was here extern int fgetpos(FILE *__restrict__, fpos_t *__restrict__); ^ In file included from /sas/data04/opt/include/python3.5m/Python.h:25:0, from numpy/core/src/umath/test_rational.c.src:6: /opt/freeware/lib/gcc/powerpc-ibm-aix6.1.0.0/4.8.3/include-fixed/stdio.h:515:12: error: conflicting types for 'fseeko64' extern int fseeko64(FILE *, off64_t, int); ^ In file included from /sas/data04/opt/include/python3.5m/Python.h:25:0, from numpy/core/src/umath/test_rational.c.src:6: /opt/freeware/lib/gcc/powerpc-ibm-aix6.1.0.0/4.8.3/include-fixed/stdio.h:455:12: note: previous declaration of 'fseeko64' was here extern int fseeko(FILE *, off_t, int); ^ -- Vinh
