Fails to link if libpng/jpeg development libraries are missing.
When compiling Tk 804.036, the following warning appears when configuring:
'pkg-config libpng' failed, continue with fallback values for cflags and libs...
This is because I have libpng16-devel installed which has libpng16.pc instead of plain libpng.pc. Because libpng was not found, the build system attempts to compile the bundled libpng. My brewed perl was compiled with _FORTIFY_SOURCE and -O2 and the build system picks up the _FORTIFY_SOURCE option, but ignores the optimization flag when compiling libpng/jpeg. This leads to the following warning when checking for <errno.h> in PNG/zlib/configure:405:
cc -c -fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/inclu
de -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2 -o example test.c
In file included from /usr/include/errno.h:25,
from test.c:1:
/usr/include/features.h:414:4: warning: #warning _FORTIFY_SOURCE requires compiling with optimization (-O) [-Wcpp]
414 | # warning _FORTIFY_SOURCE requires compiling with optimization (-O)
| ^~~~~~~
As configure checks the compiler output against the empty string, it assumes that is not found, defining the NO_ERRNO_H macro. This leads to the errno global variable being declared in PNG/zlib/zutil.h:35. This non-thread local storage variable declaration clashes with the TLS definition in the version of glibc I have installed (which is 2.39), leading to the following error when linking:
> cc -fPIC -fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2 -fPIC -DNO_snprintf -DHAS_sprintf_void -DNO_ERRNO_H -o example example.o -L. libz.a
/usr/lib64/gcc/x86_64-suse-linux/13/../../../../x86_64-suse-linux/bin/ld: errno: TLS definition in /lib64/libc.so.6 section .tbss mismatches non-TLS reference in libz.a(gzio.o)
/usr/lib64/gcc/x86_64-suse-linux/13/../../../../x86_64-suse-linux/bin/ld: /lib64/libc.so.6: error adding symbols: bad value
The fix is simple: Enable optimization by adding $Config{optimize} flag, which was -O2 on the Perl I brewed, to the CFLAGS for the bundled libpng and jpeg so that _FORTIFY_SOURCE, which was added to Perl's build system starting in 5.22, doesn't cause a warning.
diff --git a/JPEG/Makefile.jpeg.maybe b/JPEG/Makefile.jpeg.maybe
index 7bb9688b..063e53d3 100755
--- a/JPEG/Makefile.jpeg.maybe
+++ b/JPEG/Makefile.jpeg.maybe
@@ -32,7 +32,7 @@ if ($^O eq 'MSWin32')
else
{
$ENV{CC} = $Config{cc};
- local $ENV{CFLAGS} = "$Config{ccflags} $Config{cccdlflags}";
+ local $ENV{CFLAGS} = "$Config{ccflags} $Config{optimize} $Config{cccdlflags}";
local $ENV{LDFLAGS} = "$Config{ccflags} $Config{ldflags}";
system(sh => "./configure");
}
diff --git a/PNG/Makefile.zlib.maybe b/PNG/Makefile.zlib.maybe
index 6da4ba9a..abe519b8 100644
--- a/PNG/Makefile.zlib.maybe
+++ b/PNG/Makefile.zlib.maybe
@@ -26,7 +26,7 @@ if ($^O eq 'MSWin32')
else
{
$ENV{CC} = $Config{cc};
- local $ENV{CFLAGS} = "$Config{ccflags} $Config{cccdlflags}";
+ local $ENV{CFLAGS} = "$Config{ccflags} $Config{optimize} $Config{cccdlflags}";
system(sh => "./configure");
}
VERSIONS
Perl 5.41.2 (installed from source with Perlbrew)
CPAN: 1.64
GCC 13.3.0 (official Tumbleweed package)
GLIBC 2.39 (official Tumbleweed package)
openSUSE Tumbleweed 20240725-0 (Last month's snapshot)
perl-Tk version: 804.036-18-gf0bb386b
libPNG: libpng16-16 libpng16-devel
libJPEG: libjpeg8 (don't have -devel package installed at the moment)
ld.bfd version: GNU ld (GNU Binutils; openSUSE Tumbleweed) 2.42.0.20240130-4
WSL2 version:
Fails to link if libpng/jpeg development libraries are missing.
When compiling Tk 804.036, the following warning appears when configuring:
'pkg-config libpng' failed, continue with fallback values for cflags and libs...This is because I have libpng16-devel installed which has libpng16.pc instead of plain libpng.pc. Because libpng was not found, the build system attempts to compile the bundled libpng. My brewed perl was compiled with _FORTIFY_SOURCE and -O2 and the build system picks up the _FORTIFY_SOURCE option, but ignores the optimization flag when compiling libpng/jpeg. This leads to the following warning when checking for
<errno.h>in PNG/zlib/configure:405:As configure checks the compiler output against the empty string, it assumes that
errnoglobal variable being declared in PNG/zlib/zutil.h:35. This non-thread local storage variable declaration clashes with the TLS definition in the version of glibc I have installed (which is 2.39), leading to the following error when linking:The fix is simple: Enable optimization by adding
$Config{optimize}flag, which was-O2on the Perl I brewed, to the CFLAGS for the bundled libpng and jpeg so that_FORTIFY_SOURCE, which was added to Perl's build system starting in 5.22, doesn't cause a warning.VERSIONS
Perl 5.41.2 (installed from source with Perlbrew) CPAN: 1.64 GCC 13.3.0 (official Tumbleweed package) GLIBC 2.39 (official Tumbleweed package) openSUSE Tumbleweed 20240725-0 (Last month's snapshot) perl-Tk version: 804.036-18-gf0bb386b libPNG: libpng16-16 libpng16-devel libJPEG: libjpeg8 (don't have -devel package installed at the moment)
ld.bfdversion: GNU ld (GNU Binutils; openSUSE Tumbleweed) 2.42.0.20240130-4 WSL2 version:perl -V
``` Summary of my perl5 (revision 5 version 41 subversion 2) configuration: Platform: osname=linux osvers=5.15.153.1-microsoft-standard-wsl2 archname=x86_64-linux uname='linux msi 5.15.153.1-microsoft-standard-wsl2 #1 smp fri mar 29 23:14:13 utc 2024 x86_64 x86_64 x86_64 gnulinux ' config_args='-de -Dprefix=/home/nathan/perl5/perlbrew/perls/perl-5.41.2 -Dusedevel -Aeval:scriptdir=/home/nathan/perl5/perlbrew/perls/perl-5.41.2/bin' hint=recommended useposix=true d_sigaction=define useithreads=undef usemultiplicity=undef use64bitint=define use64bitall=define uselongdouble=undef usemymalloc=n default_inc_excludes_dot=define Compiler: cc='cc' ccflags ='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2' optimize='-O2' cppflags='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include' ccversion='' gccversion='13.3.0' gccosandvers='' intsize=4 longsize=8 ptrsize=8 doublesize=8 byteorder=12345678 doublekind=3 d_longlong=define longlongsize=8 d_longdbl=define longdblsize=16 longdblkind=3 ivtype='long' ivsize=8 nvtype='double' nvsize=8 Off_t='off_t' lseeksize=8 alignbytes=8 prototype=define Linker and Libraries: ld='cc' ldflags =' -fstack-protector-strong -L/usr/local/lib' libpth=/usr/local/lib /usr/x86_64-suse-linux/lib /usr/lib /usr/lib64 /usr/local/lib64 libs=-lpthread -ldl -lm -lcrypt -lutil -lc perllibs=-lpthread -ldl -lm -lcrypt -lutil -lc libc=/lib/../lib64/libc.so.6 so=so useshrplib=false libperl=libperl.a gnulibc_version='2.39' Dynamic Linking: dlsrc=dl_dlopen.xs dlext=so d_dlsymun=undef ccdlflags='-Wl,-E' cccdlflags='-fPIC' lddlflags='-shared -O2 -L/usr/local/lib -fstack-protector-strong' Characteristics of this binary (from libperl): Compile-time options: HAS_LONG_DOUBLE HAS_STRTOLD HAS_TIMES PERLIO_LAYERS PERL_COPY_ON_WRITE PERL_DONT_CREATE_GVSV PERL_HASH_FUNC_SIPHASH13 PERL_HASH_USE_SBOX32 PERL_MALLOC_WRAP PERL_OP_PARENT PERL_PRESERVE_IVUV PERL_USE_DEVEL PERL_USE_SAFE_PUTENV USE_64_BIT_ALL USE_64_BIT_INT USE_LARGE_FILES USE_LOCALE USE_LOCALE_COLLATE USE_LOCALE_CTYPE USE_LOCALE_NUMERIC USE_LOCALE_TIME USE_PERLIO USE_PERL_ATOF Built under linux Compiled at Aug 20 2024 15:21:53 %ENV: PERLBREW_HOME="/home/nathan/.perlbrew" PERLBREW_MANPATH="/home/nathan/perl5/perlbrew/perls/perl-5.41.2/man" PERLBREW_PATH="/home/nathan/perl5/perlbrew/bin:/home/nathan/perl5/perlbrew/perls/perl-5.41.2/bin" PERLBREW_PERL="perl-5.41.2" PERLBREW_ROOT="/home/nathan/perl5/perlbrew" PERLBREW_SHELLRC_VERSION="0.98" PERLBREW_VERSION="0.98" @INC: /home/nathan/perl5/perlbrew/perls/perl-5.41.2/lib/site_perl/5.41.2/x86_64-linux /home/nathan/perl5/perlbrew/perls/perl-5.41.2/lib/site_perl/5.41.2 /home/nathan/perl5/perlbrew/perls/perl-5.41.2/lib/5.41.2/x86_64-linux /home/nathan/perl5/perlbrew/perls/perl-5.41.2/lib/5.41.2 ```