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Old 09-06-2006, 11:53 AM   #1
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undefined reference to main

Hi People,

I'm getting the following error from ld (via g++ -z)

/usr/lib/gcc-lib/i386-redhat-linux/3.2.3/../../../crt1.o(.text+0x18): In function `_start':
: undefined reference to `main'

I'm at my wits end.
In anticipation of likely responses .....

1. Yes, I have defined main ... like so
int main (int argc, char * argv [])

2. It's been built - I can see the main.o

3. The link command does include the object file ...
(linker command pasted below this message)

can anyone help / make any suggestion.

I'm currently reduced to playing with the ordering of the .o's in the makefile and have the distinct feeling I'm wasting my (employers) time.

Many thanks.


g++ -z ./main.o ./smarttest_commands.o ./command_createconn.o ./command_connect.o ./command_createevent.o ./command_createmt.o ./command_destroyconn.o ./command_destroyevent.o ./command_disconnect.o ./command_namespace.o ./command_on.o ./command_ping.o ./command_publish.o ./command_reportlatencies.o ./command_reschedule.o ./command_resetlatencies.o ./command_send.o ./command_setrate.o ./command_sleep.o ./command_subscribe.o ./namespace.o ./parse.o ./ping.o ./rates.o ./smarttest_mt.o ./outgoingmessagetracker.o ./reportmissingmsgsevent.o ./smarttest_environment.o ./latency_cb.o ./incomingmessagetracker.o ./MWInterface.o ./SSInterface.o ./MWSpecificOptions.o ./command.o ./rngs.o ./rvgs.o -L../SSUtils/ -L/apps/smartsockets/smarttestdev/ss6703sc112br113/lib/i86_linux/static -L/usr/lib/gcc-lib/i386-redhat-linux/3.2.3/ -lssutils -lrtsscpp50 -lrtipc -lrtmsg -lrtsubj -lrtconn -lrtipcl -lrtedm -lrtutil -lrtsm -lnsl -lpthread -ldl -lm -lrt -lc -lstdc++ -o smarttest.x
/usr/lib/gcc-lib/i386-redhat-linux/3.2.3/../../../crt1.o(.text+0x18): In function `_start':
: undefined reference to `main'
collect2: ld returned 1 exit status
gmake: *** [smarttest.x] Error 1
Old 09-06-2006, 03:05 PM   #2
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and welcome to LQ!

Is that actually C++ code, or C?
If it's the latter, try using gcc instead of g++

Old 09-06-2006, 03:22 PM   #3
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And if you prefer to stay with g++ make sure you have
using namespace std;
Old 09-06-2006, 05:09 PM   #4
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The '-z' option expects an argument; it's using 'main.o' as that argument, and that file isn't getting linked.


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