When I run the following command from a makefile on 64-bit Red Hat Enterprise Linux 5.0 using GCC 4.2.3:
gcc -c -ansi -pedantic -O0 -fPIC -I. -I.. -Iheader_files/include "source_file.c"
I get the following error:
cc1: error: unrecognized command line option "-lang-c"
Superficially, the problem is that "-lang-c" is no longer a valid option on newer versions of GCC. However, the deeper question is: Why does GCC receive a "-lang-c" option that wasn't in the original command?
Additional background:
The current installation doesn't have any GCC "specs" files that I can find
Running "gcc -dumpspecs" produces a long list of defaults, but "-lang-c" isn't among them.
"-lang-c" does not appear to be in any environment variables that I know of that influence GCC.
Any help would be appreciated.
Regards,
Mark Biesiada
Make sure that your gcc driver program is the same version as your installed GCC.
Add the -v option to your compile command to check the versions and where the options are coming from.
Related
I am currently using the following flags for my gcc compiler:
gcc -std=c99 -pedantic -Wall D_DEFAULT_SOURCE -g -c filename.c
But how can I make the output as verbose as possible? The error messages I am getting in C are not as nice as I am used to from more high level languages and I want to get as much information out of the gcc compiler as possible.
This is a summary of all comments I've received on this post:
These flags are the best you can use to make your compiler as verbose as
possible:
-pedantic -Wall -Wextra -Wwrite-strings -g3
Other flags such as -v and the entire -d* family will make the compilation process more verbose but won't enhance the error messages you are getting.
Check your current version with gcc --version. To get the newest gcc Version (i.e. gcc 12.2 since August 19, 2022) you might have to clone the gcc repository and build it yourself based on the distro (check via lsb_release -d) you are using.
Check this stackoverflow question out to install gcc 12.2 on Ubuntu.
Alternatively you could also directly get gcc-11 from apt without upgrading to the latest bleeding edge ubuntu (don't forget to use gcc-11 instead of gcc afterwards to compile).
I have an installation of DPDK and I'm trying to compile code with it. This worked on my WSL machine, however on the test server, with the same install of dpdk, I'm getting the error:
/usr/local/include/rte_mempool.h: error: unknown type name 'ssize_t'
I've noticed this header does not include /sys/types.h, but it also doesn't include that on the machine that this works on. I don't know where it's supposed to come from, but it's coming from somewhere.
How do I get these headers to be aware of ssize_t?
As noted in a comment:
The compiler options include -std=c99 -O3 -march=native -I/usr/local/include -include rte_config.h, and a whole bunch of -l options (dpdk's make structure adds these in). This prompted me to run gcc --version and the working one is Ubuntu gcc 9.3.0 and the broken one is gcc 5.4.0. Seems like it might be an incompatibility between dpdk and the gcc installed.
As mentioned in the comments by #JonathanLeffier, the root cause of the issue is including sys/types.h when gcc option --std=c99 is passed. The easiest fix without modifying the DPDK or sample code is to include the path to types.h as part of cflags.
If the native build is for x86_64 target, follow these steps:
execute find /usr/include/ -name types.h to identify the right file for local build (this is because the current cflags has -march=native)
modify the CFLAGS from -std=c99 -O3 -march=native -I/usr/local/include -include rte_config.h to -std=c99 -O3 -march=native -I/usr/local/include -include rte_config.h --include=/usr/include/[target-machine]/sys/types.h
Note: In my humble suggestion please use pkg-config for populating the right CFLAGS and LDFLAGS for both shared and static binary.
I installed the latest version of gcc using homebrew in order to get OpenMP support, however, that is what is happening:
Sergios-MacBook:~ sergio$ gcc -fopenmp test.c -o test
clang: error: unsupported option '-fopenmp'
clang: error: unsupported option '-fopenmp'
I know that clang is the default compiler in the command line tools I have installed but I don't know what is happening and how to fix it.
If this could be of any use, I tried checking the location of gcc and got the following:
Sergios-MacBook:~ sergio$ which gcc
/usr/bin/gcc
I don't know if by default gcc is there and it is still linked to the system default one which doesn't support OpenMP
I am trying to recompile binutils and GCC as a cross-compiler for m68k architecture. I am following these instructions:
http://darkdust.net/writings/megadrive/crosscompiler
However, the process keeps failing on one part or another. I have tried with binutils 2.16.1 and gcc 3.4.6, binutils 2.15 and gcc 3.4.2 and binutils 2.15 and gcc 3.4.6.
This last attempt fails when running "make" on gcc, after making and installing binutils. It gives the following error:
gcc -g -O2 -DIN_GCC -DCROSS_COMPILE -W -Wall -Wwrite-strings -Wstrict-
prototypes -Wmissing-prototypes -pedantic -Wno-long-long -DHAVE_CONFIG_H
-I. -I. -I../../gcc-3.4.2/gcc -I../../gcc-3.4.2/gcc/. -I../../gcc-
3.4.2/gcc/../include \
-DTARGET_MACHINE=\"m68k-coff\" \
-c ../../gcc-3.4.2/gcc/collect2.c -o collect2.o
In file included from /usr/include/fcntl.h:289:0,
from ../../gcc-3.4.2/gcc/system.h:214,
from ../../gcc-3.4.2/gcc/collect2.c:30:
In function ‘open’,
inlined from ‘collect_execute’ at ../../gcc-3.4.2/gcc/collect2.c:1535:20:
/usr/include/x86_64-linux-gnu/bits/fcntl2.h:50:4: error: call to
‘__open_missing_mode’ declared with attribute error: open with O_CREAT or
O_TMPFILE in second argument needs 3 arguments
__open_missing_mode ();
^
Makefile:1364: recipe for target 'collect2.o' failed
make[1]: *** [collect2.o] Error 1
make[1]: Leaving directory '/home/gabriel/src/gcc-build/gcc'
Makefile:23339: recipe for target 'all-gcc' failed
make: *** [all-gcc] Error 2
I don't expect to fix this error, but does anyone know of a combination of binutils and gcc release that work? Should I be using a certain version of gcc to recompile gcc successfuly?
Thanks for any insight you may have on this!
EDIT:
My linux has GCC 5.4.0 so I just downloaded the 5.4.0 source to try and rebuild that for m68k cross-compiling. I now get the following error when running "make" on the gcc source:
*** Configuration m68k-unkown-coff not supported
What could be the cause of this? Is it because I need an older version of GCC? (the binutils version i'm using definately supports the m68k target). The tutorial I'm using always defines "--target=m68k-coff", should that instead be "--target=m68k-unkown-coff"?
EDIT 2:
So I tried compiling for m68k-elf but now I get this error:
checking for m68k-elf-gcc... /home/gabriel/src/gcc-build/./gcc/xgcc -B/home/gabriel/src/gcc-build/./gcc/ -B/opt/m68k/m68k-elf/bin/ -B/opt/m68k/m68k-elf/lib/ -isystem /opt/m68k/m68k-elf/include -isystem /opt/m68k/m68k-elf/sys-include
checking for suffix of object files... configure: error: in `/home/gabriel/src/gcc-build/m68k-elf/libgcc':
configure: error: cannot compute suffix of object files: cannot compile
I ran download_prerequisites before building so it should not be a problem with the MPC library. Any idea how to move on? I need assembler only so I don't mind what the format of the object files is. Thanks!
I used to do pretty much what you are doing right now.
My advice is to use crosstool-ng (http://crosstool-ng.github.io), as it does pretty much everything in an automated manner.
If you are studying m68k assembly, I used to host a modified version of gcc-explorer by Matt Godbolt (https://godbolt.org/). You can find a runnable docker image here (https://hub.docker.com/r/esantoro/acso-explorer/) and some more details here (https://znpy.wordpress.com/2017/05/08/decommisioning-acso-explorer-santoro-tk/)
Hope it helps,
znpy
you can build most versions with a current Linux. To install the prerequisites have a look at https://github.com/bebbo/amiga-gcc
unpack the gcc archive, e.g. to /opt/cross/gcc-6.5.0
create a separate build folder, e.g. /opt/cross/xcc-6.5.0 - never build inside gcc's source folder!
create the prefix folder, that's where binaries are installed to, e.g. /opt/cross/gcc65
ensure that these folders exist and are writable, then
configure from within that build folder using an absolute path for configure
cd /opt/cross/xcc-6.5.0/
/opt/cross/gcc-6.5.0/configure --target=m68k-elf --program-prefix=m68k-elf- --enable-languages=c,c++ --prefix=/opt/cross/gcc65 --disable-libssp --disable-nls --disable-multilib
make all-gcc
make install-gcc
I'm also running the compiler explorer for 68k gccs at https://franke.ms/cex/
I got a gcc compilation error:
gcc-4.9: error: unrecognized command line option '-rdynamic'
and I tested compilation with -rdynamic in some environments. While I used the same version of gcc (4.9.2), in some environments gcc worked well, but others (e.g. Homebrew gcc 4.9.2_1, cygwin 64bit) not. What makes the difference?
-rdynamic passes the flag -export-dynamic to ELF linker, on targets that support it.
Executable formats in OS X and Windows are not ELF, thus the option -rdynamic is not supported building for these operating systems.