| Title: | DIGITAL UNIX (FORMERLY KNOWN AS DEC OSF/1) |
| Notice: | Welcome to the Digital UNIX Conference |
| Moderator: | SMURF::DENHAM |
| Created: | Thu Mar 16 1995 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 10068 |
| Total number of notes: | 35879 |
Hi I have a customer who had a question about ld and the -om switch "We are using the Apex compiler supplied by Rational to build Ada 83 >executables under DEC UNIX 3.2X/4.0X. The build environment calls the DEC >linker, ld. Depending on the switches used to compile, ld appears to be >called either directly or via cc. I have found some information from DEC on >the -om switch which performs post-link optimisation. I thought this might >work on executables generated from Ada 83 as by post-link time no matter what >the original source I'd expect the exe to be in DEC's extended COFF. I passed >the -om switch to the Rational compiler which in turn passed it to ld. The >link phase finished without error report. Examination of the exe with the >size -A command revealed that several sections of the executable had been >either removed or substantially reduced in size. Unfortunately, the exe >dumped core when run. (It ran perfectly well before I let -om loose on it.) > >So I guess I need to know if I can use -om on executables generated from Ada >83. The cc man page does say that the -om switch must be used with cc. I >think I can sort out the Apex environment so that Apex calls cc with this >switch at build. But will this object modification stuff work with Ada >executables?" Has anyone got any suggestions etc? Thanks Adrian [Posted by WWW Notes gateway]
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 9861.1 | QUARRY::neth | Craig Neth | Mon May 19 1997 11:10 | 27 | |
ld -om doesn't actually run om, the post-link optimizer; all it does is prepare the input file so that the /usr/lib/cmplrs/cc/om image can be run on it. So it's not suprising that using ld -om by iteself didn't give you anything useful. Here's what 'cc -om' does: > cc hello.c -om -non_shared -v /usr/lib/cmplrs/cc/gemc_cc -D__LANGUAGE_C__ -D__unix__ -D__osf__ -D__alpha -D_SYSTYPE_BSD -D_LONGLONG -D__digital__ -D__arch64__ -DLANGUAGE_C -Dunix -DSYSTYPE_BSD -I/usr/include -preempt_module -g0 -O2 -std0 -o hello.o hello.c /usr/lib/cmplrs/cc/gemc_cc: 0.07u 0.02s 0:00 56% 0+8k 0+20io 0pf+0w 8stk+1216mem /usr/lib/cmplrs/cc/ld -g0 -O1 -non_shared /usr/lib/cmplrs/cc/crt0.o hello.o -lc -om -o /tmp/ctmomaaunwa /usr/lib/cmplrs/cc/ld: 0.02u 0.05s 0:01 5% 0+7k 136+41io 0pf+0w 7stk+1216mem /usr/lib/cmplrs/cc/om /tmp/ctmomaaunwa -g0 -O1 -non_shared /usr/lib/cmplrs/cc/om: 0.48u 0.04s 0:00 57% 0+15k 68+25io 0pf+0w 15stk+1936mem So, you need to find a way (either by using cc -om) or just directly running the om image on the output of the ld -om command. I am not aware of any problems with using om with Apex ADA, but I'm not sure I know of anybody using the two together either. Let us know how things come out. | |||||