rpidmx512: undefined reference to `memcpy'?

Hey Arjan,

No stress, i’m messing around, but I am getting the weirdest thing… Well I don’t understand anyway.

I know it’s 3rd party, but I am trying some code from the project microui which is a tiny, (C but reports C++ compilable) like 1K lines of code, it’s a very basic window and widget framework. It’s very lightweight, only needs memcpy, memset, strtod & qsort. and i’ve read through all the code and can’t see any calls that raise suspicion.

I’ve had to implement strtod and qsort with some codes I found, and read them carefully and they seem all good too.

I have worked hard, and have gotten down to just this error from so many, where it can’t find memcpy when linking 😃 I’ve tried including string.h, and many other things, all day.

[/home/hip/dev/new/rpidmx512/lib-arm]
$DEFINES [-DORANGE_PI_ONE  -DNDEBUG -D_TIME_STAMP_YEAR_=2020 -D_TIME_STAMP_MONTH_=8 -D_TIME_STAMP_DAY_=13]
$MAKE_FLAGS [-DCONSOLE_FB]
$BUILD_DIRS [build_h3/src build_h3/src/h3]
$TARGET [lib_h3/libarm.a ]
arm-none-eabi-ar: creating lib_h3/libarm.a
arm-none-eabi-ld: build_h3/lib/microui.o: in function `mu_init(mu_Context*)':
microui.cpp:(.text+0x144): undefined reference to `memcpy'
arm-none-eabi-ld: build_h3/lib/microui.o: in function `push_layout(mu_Context*, mu_Rect, mu_Vec2)':
microui.cpp:(.text+0x1848): undefined reference to `memcpy'
make: *** [../h3-firmware-template/Rules.mk:221: build_h3/main.elf] Error 1

and in the map file, there are only references to h3_memcpy.

I change every call to ui_memcpy() and implement that in the microui.cpp file, and it still dies here looking for memcpy?

I have a branch in my fork here https://github.com/hippyau/rpidmx512/tree/experimental-ui

Any ideas?

About this issue

Original URL
State: closed
Created 4 years ago
Comments: 18 (18 by maintainers)

Most upvoted comments

All good, thanks so much for your help @vanvught and @rewolff !!

hippyau on Aug 14, 2020

(C but reports C++ compilable)

Well… it is missing

#ifdef __cplusplus
extern "C" {
#endif

in https://github.com/rxi/microui/blob/master/src/microui.h

#ifdef __cplusplus
}
#endif

vanvught on Aug 13, 2020

Hi Hippy,

memcpy is defined in string.h

microui.c does include <string.h>

So I am not sure why do you get this error.

The h3_memcpy should be used in low-level routines only -> lib-h3

As it is all ANSI-C , then leave the extension of the files just with *.c

And make sure that you have

#ifdef __cplusplus
extern "C" {
#endif

....

#ifdef __cplusplus
}
#endif

around the C prototypes.

Please be aware of the global settings: COPS+=-nostartfiles -ffreestanding -nostdinc -nostdlib

Greetings, Arjan

vanvught on Aug 13, 2020

Some memcpy calls are generated by the compiler.

struct somestruct a, b ;

b = a;

Maybe more. Best course of action would be to provide a memcpy. If you’re not calling it you can hope it doesn’t get called too often, so an implementation would only be a few lines if you don’t care about performance.

rewolff on Aug 13, 2020