[SOLVED] gcc: not sufficient memory to compile, even with -O2 ?

Xeratul · 09-21-2014, 01:59 PM

Hello, Good morning,

I would like to compile a C program with visibly not sufficiently enought main memory. My machine has the following 256MB DDR-333 SDRAM, 166MHz under Linux Debian Testing.

I have tried with the option -O2 but it still can not compile the C code.

I am out of luck.

I would be pleased if you could tell me how to compile with this given machine.

I hope so much that you would have any further ideas or tricks.

Thank you so much by advance.

business_kid · 09-21-2014, 02:07 PM

Check for adequate swap space, close off _everything_ not needed for the compile. I ran out once on a link - the compile was ok. I had 128M and 64M of swap, and it used them all before crapping out. Closing everything got me through, but it used 197MB of ram&swap - pretty close!

You need a console, runlevel 3, all background stuff closed. No X, no nothing.

If the gcc command breaks down, it's probably a problem with the software. If it's the link (ld), it may just be linked to too many libs.

metaschima · 09-21-2014, 02:15 PM

You probably do need more swap to be able to compile large programs or libraries on such a machine.

NevemTeve · 09-21-2014, 02:22 PM

+1 for swap.
Also, if it is your program, check the size of the source: a compilation unit shouldn't be bigger than a few hundred lines.

Xeratul · 09-21-2014, 02:50 PM

Thank you for first replies.

I am actually not using a swap (partition) on this machine. There is no swap, only ext2 with / and ext3 with /home. Ok. So let's bring a swap:

I could plug an USB harddrive of 1 TeraBytes. Format it to Swap (create it maybe with fdisk if it works) and edit the /etc/fstab to mount it as swap. (I have to check how on google).
Would you think that it would work, i.o.w. that gcc would work and would compile?

I looking forward to reading you.

Thank you in advance.

metaschima · 09-21-2014, 03:07 PM

It should work, but I would put swap on the main HDD whenever possible, otherwise you'll have to turn it on manually every time. On such a low RAM machine you need swap. I only run without swap on machines with at least 2-4 GB of RAM.

NevemTeve · 09-21-2014, 10:51 PM

Note: you can use swap-files too, no only swap-partitions.

pan64 · 09-22-2014, 12:21 AM

one additional comment: using -O2 will force the compiler to eat more memory, without optimization it needs less...

Xeratul · 09-30-2014, 02:00 PM

Sorry for my relatively late answer. I have been quite busy.

I would like to thank you !!

This method of adding a swap was the key to success.

I used gparted, and created a swap partition on an 8gb pendrive.
I configured /etc/fstab and mount using swap -a when I need to compile (somtimes)

It works (no need of -O2 even)!! Just the swap is sufficient to compile. finally.

Thank you !!!