[PATCH] Link with -ldl on GNU/kFreeBSD

[PATCH] Link with -ldl on GNU/kFreeBSD

[peter]

GNU/kFreeBSD uses the FreeBSD kernel with the GNU C library.
---
 cgit.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cgit.mk b/cgit.mk
index 369f309..35e40dc 100644
--- a/cgit.mk
+++ b/cgit.mk
@@ -54,7 +54,7 @@ endif
 endif
 
 # Add -ldl to linker flags on non-BSD systems.
-ifeq ($(findstring BSD,$(uname_S)),)
+ifeq (,$(filter $(uname_S),DragonFly FreeBSD NetBSD OpenBSD))
 	CGIT_LIBS += -ldl
 endif
 
-- 
2.8.1

[PATCH] Link with -ldl on GNU/kFreeBSD

[Jason]

Hey Peter,

I wonder if a better way would be match the particular libc out of
uname -o. In this case, GNU libc needs -ldl. Do other libcs also need
libdl? Seems like this might be slightly cleaner.

Any opinions on this list?

Jason

[PATCH] Link with -ldl on GNU/kFreeBSD

[peter]

On Fri, Jul 01, 2016 at 11:56:55PM +0200, Jason A. Donenfeld wrote:
> I wonder if a better way would be match the particular libc out of
> uname -o. In this case, GNU libc needs -ldl. Do other libcs also need
> libdl? Seems like this might be slightly cleaner.

In theory one could detect glibc by grepping for specific macros,

cc -E -dM -include dlfcn.h -xc /dev/null

but in practice other libcs pretend being glibc:

https://git.uclibc.org/uClibc/tree/include/features.h

/*  There is an unwholesomely huge amount of code out there that depends on the
 *  presence of GNU libc header files.  We have GNU libc header files.  So here
 *  we commit a horrible sin.  At this point, we _lie_ and claim to be GNU libc

Peter

[PATCH] Link with -ldl on GNU/kFreeBSD

[peter]

On Sun, Jun 19, 2016 at 06:55:53PM -0400, Peter Colberg wrote:
> +ifeq (,$(filter $(uname_S),DragonFly FreeBSD NetBSD OpenBSD))
>  	CGIT_LIBS += -ldl
>  endif

LuaJIT adds -ldl for specific OSes, which seems a better choice:

https://github.com/LuaJIT/LuaJIT/blob/master/src/Makefile

  ifeq (Linux,$(TARGET_SYS))
    TARGET_XLIBS+= -ldl
  endif
  ifeq (GNU/kFreeBSD,$(TARGET_SYS))
    TARGET_XLIBS+= -ldl
  endif

I will post a revised patch.

Peter

[PATCH v2] Link with -ldl on GNU/kFreeBSD

[peter]

GNU/kFreeBSD uses the FreeBSD kernel with the GNU C library.

Signed-off-by: Peter Colberg <peter at colberg.org>
---
 cgit.mk | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cgit.mk b/cgit.mk
index 369f309..8d4f5e0 100644
--- a/cgit.mk
+++ b/cgit.mk
@@ -53,8 +53,8 @@ endif
 
 endif
 
-# Add -ldl to linker flags on non-BSD systems.
-ifeq ($(findstring BSD,$(uname_S)),)
+# Add -ldl to linker flags on systems that commonly use GNU libc.
+ifneq (,$(filter $(uname_S),Linux GNU/kFreeBSD))
 	CGIT_LIBS += -ldl
 endif
 
-- 
2.8.1

[PATCH v2] Link with -ldl on GNU/kFreeBSD

[peter]

On Fri, Jul 01, 2016 at 10:00:37PM -0400, Peter Colberg wrote:
> GNU/kFreeBSD uses the FreeBSD kernel with the GNU C library.
> 
> Signed-off-by: Peter Colberg <peter at colberg.org>
> ---
>  cgit.mk | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/cgit.mk b/cgit.mk
> index 369f309..8d4f5e0 100644
> --- a/cgit.mk
> +++ b/cgit.mk
> @@ -53,8 +53,8 @@ endif
>  
>  endif
>  
> -# Add -ldl to linker flags on non-BSD systems.
> -ifeq ($(findstring BSD,$(uname_S)),)
> +# Add -ldl to linker flags on systems that commonly use GNU libc.
> +ifneq (,$(filter $(uname_S),Linux GNU/kFreeBSD))
>  	CGIT_LIBS += -ldl
>  endif
>  
> -- 
> 2.8.1
> 

Any objections to merging this? While it is not a perfect solution,
it is better than the status quo and allows Debian to drop a patch.

Peter

[PATCH v2] Link with -ldl on GNU/kFreeBSD

[Jason]

Seems like a more sensible approach. I'll merge this and see if
anybody complains.