Wednesday, July 06, 2011

compile mpich2

If you are using gcc version >= 4.3 to compile mpich2-1.3, which can be downloaded from, you are likely to get tons of multiple definition errors. It took me quite a while to figure out the reason and the solution. This is caused by the --std=gnu99 used in hwloc. But using gnu99 will change the meaning of "extern inline" used in many c header files as explained in Knowing this, the solution is quite simple: using the following command to configure:

CFLAGS=-fgnu89-inline ./configure

Wednesday, April 13, 2011

Effective alternative minimum tax bracket

2010 AMT bracket for the alternative minimum taxable income (AMT income)
assumming no qualified dividend or long term capital gain.


The strange thing is that the tax rate decreases for high AMT income. This is due to the fact that the "Exemption Amount" (Form 6251 line 29) is reduced when the AMT income is between 150,000 and 439,800.


Form 6251

Form 6251 Instruction