in reply to Re^2: problem installing DBD::Pg
in thread problem installing DBD::Pg

Are you sure about the line number 3242 ?

Sorry - it hadn't occurred to me that Pg.c was (as Tux has just pointed out) a generated file.

The problem arises because of the declaration of static int errno; in Pg.h. (This declaration is made only on Windows.)
I would first try removing that declaration (line 14) from Pg.h and then rebuild DBD::Pg afresh.
Here's a simple demo of the problem:

UPDATE: In this demo script, I originally declared foo() as SV * foo().
I have now corrected that declaration to void foo(). 
use strict;
use warnings;

use Inline C => <<'END_OF_C';

static int errno;

void foo() {
  printf("errno: %d\n", errno);
}

END_OF_C

foo();

[download]
On Windows, running that perl script with my Platform SDK compiler (14.00.40310.41), I get: 

Microsoft (R) Program Maintenance Utility   Version 7.00.8882
Copyright (C) Microsoft Corp 1988-2000. All rights reserved.

--snip--

    cl -c  -I"C:/_32/pscrpt/inline"  -nologo -GF -W3 -MD -Zi -DNDEBUG 
+-Ox -GL -fp:precise -DWIN32 -D_CONSOLE -DNO_STRICT -DWIN64 -DCONSERVA
+TIVE -DPERL_TEXTMODE_SCRIPTS -DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONT
+EXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -MD -Zi -DNDEBUG -Ox -GL -fp:pre
+cise    -DVERSION=\"0.00\"  -DXS_VERSION=\"0.00\"  "-IC:\_64\ap1600\l
+ib\CORE"   try_pl_3645.c
try_pl_3645.c
try_pl_3645.c(210) : error C2129: static function 'int *_errno(void)' 
+declared but not defined
        C:\_64\Platform_SDK\Include\crt\errno.h(54) : see declaration 
+of '_errno'
NMAKE : fatal error U1077: 'cl' : return code '0x2'
Stop.

A problem was encountered while attempting to compile and install your
+ Inline
C code. The command that failed was:
  C:\_64\PLATFO~1\Bin\nmake.exe > out.make 2>&1

The build directory was:
C:\_32\pscrpt\inline\_Inline\build\try_pl_3645

To debug the problem, cd to the build directory, and inspect the outpu
+t files.

 at try.pl line 12.
    ...propagated at C:/_64/ap1600/site/lib/Inline/C.pm line 772.
BEGIN failed--compilation aborted at try.pl line 12.

[download]
I get the same problem with mingw (gcc) compilers - with slightly different error messages.

There's only the one instance of "errno" in the entire DBD::Pg source, so I'm guessing there's no harm in removing that one and only instance at line 14 of Pg.h.
Or am I missing something ?

Cheers,
Rob

Replies are listed 'Best First'.
Re^4: problem installing DBD::Pg
by Anonymous Monk on Jan 23, 2020 at 08:59 UTC
[reply]
      So add something like #if _MSC_VER == 1200 ... #endif so its only added where it was historically needed

      I have Visual Studio 6.0 and I have an ActiveState build of perl-5.16.0 that was built with Visual Studio 6.0.
      I see exactly the same behaviour when I run my Inline::C script on that build of perl, using Visual Studio 6.0.

      I can't see that the inclusion of that static declaration would ever have been anything other than a fatal build-time error.
      And yet, DBD::Pg-3.8.0 (which includes that static declaration) ships with latest Strawberry Perl.
      Did Strawberry Perl developers remove that declaration in order to build DBD::Pg ?
      Could someone check http://strawberryperl.com/package/kmx/perl-modules-patched/ and see if there's any mention of patches to DBD::Pg. (I'm unable to access that page.)

      Cheers,
      Rob
[reply]
[d/l]
        strawberry-patched $ cat DBD-Pg-3.7.4_patched.diff
diff -ru DBD-Pg-3.7.4/Pg.h DBD-Pg-3.7.4_patched/Pg.h
--- DBD-Pg-3.7.4/Pg.h   2018-02-04 17:02:47.000000000 +0100
+++ DBD-Pg-3.7.4_patched/Pg.h   2018-04-07 17:59:19.010783900 +0200
@@ -14,9 +14,11 @@
 static int errno;
 #include <string.h>
 #define strcasecmp(s1,s2) stricmp((s1), (s2))
+#ifndef __USE_MINGW_ANSI_STDIO
 #ifndef snprintf
 #define snprintf _snprintf
 #endif
+#endif
 #else
 #include <strings.h>
 #endif

        [download]

        Enjoy, Have FUN! H.Merijn
[reply]
[d/l]

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