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In the past I have embedded resource files (images) into programs by first converting them to .o files using the GNU linker. For example:

ld -r -b binary -o file.o file.svg

Starting with FreeBSD 12, the default linker has changed from GNU's to LLVM's. Although the linker appears to understand the command line options, it results in an error. For example:

ld -r -b binary -o file.o file.svg

ld: error: target emulation unknown: -m or at least one .o file required

Also tried using the command line options from the ld.lld(1) manual page:

ld --relocatable --format=binary -o file.o file.svg

ld: error: target emulation unknown: -m or at least one .o file required

Am I using the correct tool? Do I need to specify a value for the -m option?

Is it really worth the trouble? That wasn't portable in the first place.

You should better convert your .svg to a C char array; Example:

$ cat Makefile

.SUFFIXES: .svg

.svg.c:

        od -tx1 $< | sed 's/ /,0x/g;s/[^,]*//;1s/,/char $*={/;$$s/$$/};/' > $@



$ make file.o

od -tx1 file.svg | sed 's/ /,0x/g;s/[^,]*//;1s/,/char file={/;$s/$/};/' > file.c

cc    -c -o file.o file.c

rm file.c

Of course, you can set the name of the array to something different / more robust (eg. char $(subst /,_,$*) = ... instead of char $* = ... with GNU make). Also, you could build an ad-hoc bin2c converter written in C instead of that horrible od+sed combo.

It seems you need to add -z noexecstack (This was added for ELF binaries as well in LLD 7.0.0). The default is to have an executable stack region which is vulnerable to exploitation via stack memory. Your binary image does not have an executable stack and I believe that is why it fails. The error throws you off as it asks you to tell what target emulation to use for your stack (which you do not have).

David Herrmann did all the hard work and have found a cross platform solution which covers:

• GNU-ld


• GNU-gold


• GNU-libtool


• work with cross-compiling


• work with LLVM


• do not require any external non-standard tools

The magic invocation is then:

$(LD) -r -o "src/mydata.bin.o" -z noexecstack --format=binary "src/mydata.bin"

And most often you want that binary segment to be read-only:

$(OBJCOPY) --rename-section .data=.rodata,alloc,load,readonly,data,contents "src/mydata.bin.o"

After looking through the source, the correct target emulation for my platform is elf_amd64. So the conversion from binary to object file works using:

ld -r -b binary -m elf_amd64 -o file.o file.svg