[Buildroot] [PATCH] package/lshw: fix musl build

[Romain Naour]

Hi Thomas,

Le 04/08/2016 à 20:09, Thomas Petazzoni a écrit :
> Hello,
> 
> On Thu, 4 Aug 2016 19:09:25 +0200, Romain Naour wrote:
> 
>> Actually, I get an error on basename from sysfs.cc
>>
>> sysfs.cc: In function ‘std::string sysfs_getbustype(const string&)’:
>> sysfs.cc:103:41: error: invalid conversion from ‘const char*’ to ‘char*’
>> [-fpermissive]
>>        "/devices/" + basename(path.c_str());
>>
>> The cast in dasd is not necessary.
> 
> Are you sure it's musl related, and not gcc version related? A
> -fpermissive error typically indicates that the compiler has become
> stricter than it used to be.

It seems related to musl. lshw build fine with a toolchain with gcc 5.

I'm not a glibc expert but it seems that glibc accept a char * or const char *
as filename argument, see string.h from glibc:

#  ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
extern "C++" char *basename (char *__filename)
     __THROW __asm ("basename") __nonnull ((1));
extern "C++" const char *basename (const char *__filename)
     __THROW __asm ("basename") __nonnull ((1));
#  else
extern char *basename (const char *__filename) __THROW __nonnull ((1));
#  endif
# endif

The musl version doesn't support the const char * prototype.

Also, the lshw code expect the GNU version of basename(). But this version is
not available from string.h when C++ is used.

See string.h from musl:
#ifndef __cplusplus
char *basename();
#endif

That's the issue reported by autobuilders, so the only way is to use the POSIX
basename() if we want to use lshw with musl.

Upstream fixed a similar issue in src/core/pci.cc using the POSIX basename() [1]
and a cast from const char * to char * to avoid invalid conversion.

Thought ?

Best regards,
Romain

[1] https://github.com/lyonel/lshw/commit/cd690bff1516b40fecd5ec4a7f6619e5bffc3cf0

> 
> Thomas
>