commit 345d607e7958b7f31d5f0c780e86d1cc3e658d99
Author: Niko Tyni <ntyni@debian.org>
Date:   Tue Apr 14 22:55:34 2009 +0300

    Squelch 'Constant subroutine ... undefined' warnings from .ph files
    
    As reported by Christopher Zimmermann in <http://bugs.debian.org/379757>,
    code generated from simple #undef directives by h2ph can cause
    'Constant subroutine ... undefined' warnings if the undefined
    function was eligible for inlining.
    
    (cherry picked from commit c0cc52e96e988526754ef533bd76595720660db2)

commit 2d375d52dd1895b26a80209dd64a3c11b9e3b532
Author: Niko Tyni <ntyni@debian.org>
Date:   Tue Apr 14 22:55:33 2009 +0300

    Add tests to verify that h2ph output compiles and is warning free
    
    The #include directives are #ifdef'd out so that running the
    resulting code does not actually need the headers. We still
    get the same effect from comparing with the expected h2ph output.
    
    (cherry picked from commit c1a2df7619e7315b8fccef3b9fa56bb8d7df3845)

diff --git a/lib/h2ph.t b/lib/h2ph.t
index 7b339b3..e303406 100755
--- a/lib/h2ph.t
+++ b/lib/h2ph.t
@@ -15,7 +15,7 @@ if (!(-e $extracted_program)) {
     exit 0;
 }
 
-print "1..2\n";
+print "1..4\n";
 
 # quickly compare two text files
 sub txt_compare {
@@ -32,6 +32,14 @@ print(($ok == 0 ? "" : "not "), "ok 1\n");
 $ok = txt_compare("lib/h2ph.ph", "lib/h2ph.pht");
 print(($ok == 0 ? "" : "not "), "ok 2\n");
     
+# does the output compile?
+$ok = system($^X, "-I../lib", "lib/h2ph.pht");
+print(($ok == 0 ? "" : "not "), "ok 3\n");
+
+# is the output warning free?
+$ok = system($^X, "-w", "-I../lib", "-e", '$SIG{__WARN__} = sub { die $_[0] }; require "lib/h2ph.pht"');
+print(($ok == 0 ? "" : "not "), "ok 4\n");
+
 # cleanup - should this be in an END block?
 unlink("lib/h2ph.ph");
 unlink("_h2ph_pre.ph");
diff --git a/t/lib/h2ph.h b/t/lib/h2ph.h
index 495789a..78429ca 100644
--- a/t/lib/h2ph.h
+++ b/t/lib/h2ph.h
@@ -26,6 +26,10 @@
 #undef MAX
 #define MAX(a,b) ((a) > (b) ? (a) : (b))
 
+/* Test #undef'ining an existing constant function */
+#define NOTTRUE 0
+#undef NOTTRUE
+
 /* Test #ifdef */
 #ifdef __SOME_UNIMPORTANT_PROPERTY
 #define MIN(a,b) ((a) < (b) ? (a) : (b))
@@ -68,9 +72,11 @@ function Tru64_Pascal(n: Integer): Integer;
  *  with `use lib qw(/opt/perl5/lib/site_perl/i586-linux/linux);' or whatever
  *  your equivalent is...
  */
+#if 0
 #include <sys/socket.h>
 #import "sys/ioctl.h"
 #include_next <sys/fcntl.h>
+#endif
 
 /* typedefs should be ignored */
 typedef struct a_struct {
diff --git a/t/lib/h2ph.pht b/t/lib/h2ph.pht
index 145e682..3723fca 100644
--- a/t/lib/h2ph.pht
+++ b/t/lib/h2ph.pht
@@ -1,6 +1,6 @@
 require '_h2ph_pre.ph';
 
-no warnings 'redefine';
+no warnings qw(redefine misc);
 
 unless(defined(&SQUARE)) {
     sub SQUARE {
@@ -22,6 +22,8 @@ unless(defined(&_H2PH_H_)) {
         my($a,$b) = @_;
 	    eval q((($a) > ($b) ? ($a) : ($b)));
     }' unless defined(&MAX);
+    eval 'sub NOTTRUE () {0;}' unless defined(&NOTTRUE);
+    undef(&NOTTRUE) if defined(&NOTTRUE);
     if(defined(&__SOME_UNIMPORTANT_PROPERTY)) {
 	eval 'sub MIN {
 	    my($a,$b) = @_;
@@ -47,15 +49,17 @@ unless(defined(&_H2PH_H_)) {
     } else {
 	eval 'sub WHATEVER () {1000;}' unless defined(&WHATEVER);
     }
-    require 'sys/socket.ph';
-    require 'sys/ioctl.ph';
-    eval {
-	my(@REM);
-	my(%INCD) = map { $INC{$_} => 1 } (grep { $_ eq "sys/fcntl.ph" } keys(%INC));
-	@REM = map { "$_/sys/fcntl.ph" } (grep { not exists($INCD{"$_/sys/fcntl.ph"}) and -f "$_/sys/fcntl.ph" } @INC);
-	require "$REM[0]" if @REM;
-    };
-    warn($@) if $@;
+    if(0) {
+	require 'sys/socket.ph';
+	require 'sys/ioctl.ph';
+	eval {
+	    my(@REM);
+	    my(%INCD) = map { $INC{$_} => 1 } (grep { $_ eq "sys/fcntl.ph" } keys(%INC));
+	    @REM = map { "$_/sys/fcntl.ph" } (grep { not exists($INCD{"$_/sys/fcntl.ph"}) and -f "$_/sys/fcntl.ph" } @INC);
+	    require "$REM[0]" if @REM;
+	};
+	warn($@) if $@;
+    }
     eval("sub sun () { 0; }") unless defined(&sun);
     eval("sub mon () { 1; }") unless defined(&mon);
     eval("sub tue () { 2; }") unless defined(&tue);
diff --git a/utils/h2ph.PL b/utils/h2ph.PL
index 6f40126..4e99a7a 100644
--- a/utils/h2ph.PL
+++ b/utils/h2ph.PL
@@ -123,7 +123,7 @@ while (defined (my $file = next_file())) {
 
     print OUT
         "require '_h2ph_pre.ph';\n\n",
-        "no warnings 'redefine';\n\n";
+        "no warnings qw(redefine misc);\n\n";
 
     while (defined (local $_ = next_line($file))) {
 	if (s/^\s*\#\s*//) {