Add a paragraph about an optimization bug in SGI compilers which affects

complex objects, and explain how to build so that Objects/complexobject.c
is compiled without optimization.

Closing SourceForge bug #110695 as "Won't Fix".

diff --git a/README b/README
index dd86dfce2965bd017aed51318e4472f444e27c41..579646554a0b6cbc1bee61e9baac2959497ef163 100644 (file)
--- a/README
+++ b/README
@@ -374,6 +374,13 @@ SGI:       SGI's standard "make" utility (/bin/make or /usr/bin/make)
        you set the first line of the Makefile to #!/usr/sbin/smake
        smake will be invoked by make (likewise for GNU make).
 
+       There is a bug in the SGI compiler's optimization that causes a
+       bus error in PyComplex_ImagAsDouble(); this has been reported to
+       be triggered when importing Numeric Python and may be caused at
+       other times.  The work-around is to build Python, delete the
+       Objects/complexobject.o file, and then recompile without
+       optimization (use "make OPT=").
+
 OS/2:   If you are running Warp3 or Warp4 and have IBM's VisualAge C/C++
         compiler installed, just change into the pc\os2vacpp directory
         and type NMAKE.  Threading and sockets are supported by default