Hi Bruce, thanks, the second variant is indeed easy! Is there any advantage to create a cross-file instead of just passing an option to compiler and linker and specifying pkg-config libdir? or would it be more "canonical"?
Kind regards, Renata ________________________________ From: Bruce Richardson <[email protected]> Sent: Tuesday, October 13, 2020 6:04 PM To: Renata Saiakhova <[email protected]> Cc: [email protected] <[email protected]> Subject: Re: Compiling 32-bit dpdk with meson in 64-bit container On Tue, Oct 13, 2020 at 03:54:13PM +0000, Renata Saiakhova wrote: > Hi all, hi Bruce, > > I have an issue to compile 32 bit dpdk (version 20.08) with meson in a > 64-bit container. > > As I can see from meson.build, it deducts the arch from the cc sizeof: > > dpdk_conf.set('RTE_ARCH_64', cc.sizeof('void *') == 8) > > The attempts to workaround it and set RTE_ARCH_64 to false gives good > values in build/rte_build_config.h: > > #define RTE_ARCH i686 > #undef RTE_ARCH_64 > #define RTE_ARCH_I686 1 > #define RTE_ARCH_X86 1 > #define RTE_CACHE_LINE_SIZE 64 > but, nevertheless, dpdk is compiled for 64 bit and not for 32 bit. > Before, with make build system, RTE_ARCH_ values defined arch and > compilation flags for x86 (like -m32 for i686), but with meson it seems > to be more complicated? > Is there a way to compile 32 bit dpdk (version 20.08) with meson in a > 64-bit environment? > Kind regards, > Renata Hi Renata, there are two ways to do this - firstly one can create and use a cross-file, but secondly, and easier, one just needs to tell the compiler to create 32-bit binaries using the -m32 flag. In this second case, the only additional complication is that you need to ensure that pkg-config looks for the relevant .pc files in a 32-bit lib directory rather than a 64-bit one. Based on that, on my Ubuntu system, the following commands will work to do a 32-bit build of DPDK: $ PKG_CONFIG_LIBDIR=/usr/lib/i386-linux-gnu/pkgconfig/ meson -Dc_args='-m32' \ -Dc_link_args='-m32' build-32bit $ ninja -C build-32bit Checking the resulting binary: $ file build-32bit/app/dpdk-testpmd build-32bit/app/dpdk-testpmd: ELF 32-bit LSB shared object, Intel 80386, \ version 1 (SYSV), dynamically linked, ... Depending on your Linux distribution, the pkg-config libdir you need to specify may be different, e.g. /usr/lib32/pkgconfig, perhaps. Note also that it's the "_LIBDIR" variable rather than "PKG_CONFIG_PATH" that must be set, since the latter just appends to the search paths rather than replacing them with 32-bit versions. Regards, /Bruce
