30 Apr
2019
30 Apr
'19
3:53 p.m.
On 4/29/19 6:18 PM, Arnaldo Carvalho de Melo wrote:
Ok, I'll improve that, I think
it just tries to detect a libc, yeah,
see:
[acme@quaco linux]$ cat tools/build/feature/test-glibc.c
// SPDX-License-Identifier: GPL-2.0
#include <stdlib.h>
#if !defined(__UCLIBC__)
#include <gnu/libc-version.h>
#else
#define XSTR(s) STR(s)
#define STR(s) #s
#endif
int main(void)
{
#if !defined(__UCLIBC__)
const char *version = gnu_get_libc_version();
#else
const char *version = XSTR(__GLIBC__) "." XSTR(__GLIBC_MINOR__);
#endif
return (long)version;
}
[acme@quaco linux]$
[perfbuilder@59ca4b424ded /]$ grep __GLIBC__
/arc_gnu_2017.09-rc2_prebuilt_uclibc_le_arc700_linux_install/arc-snps-linux-uclibc/sysroot/usr/include/*.h
/arc_gnu_2017.09-rc2_prebuilt_uclibc_le_arc700_linux_install/arc-snps-linux-uclibc/sysroot/usr/include/features.h:
The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are
/arc_gnu_2017.09-rc2_prebuilt_uclibc_le_arc700_linux_install/arc-snps-linux-uclibc/sysroot/usr/include/features.h:#define __GLIBC__ 2
/arc_gnu_2017.09-rc2_prebuilt_uclibc_le_arc700_linux_install/arc-snps-linux-uclibc/sysroot/usr/include/features.h: ((__GLIBC__
<< 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
[perfbuilder@59ca4b424ded /]$
Isn't that part of uClibc?
Right you are. Per the big fat comment right above that code, this gross hack in
uclibc is unavoidable as applications tend to rely on that define.
So a better fix would be to check for various !GLIBC libs explicitly.
#ifdef __UCLIBC__
#elseif defined __MUSL__
...
Not pretty from app usage pov, but that seems to be the only sane way of doing it.
-Vineet
Auto-detecting system features:
... dwarf: [ OFF ]
... dwarf_getlocations: [ OFF ]
... glibc: [ on ]
Not related to current issue, this run
uses a uClibc toolchain and yet it is
detecting glibc - doesn't seem right to me.