[Pkg-samba-maint] Bug#939618: tevent FTCBFS: multiple reasons

[Helmut Grohne]

Source: tevent
Version: 0.9.39-2
Tags: patch
User: debian-cross at lists.debian.org
Usertags: cross-satisfiability ftcbfs

tevent fails to cross build from source for many reasons.

1. The python3 build dependency is not installable, because it is
   interpreted as a host dependency. We really want a build architecture
   python here for running waf though, so it should be annotated with
   :any or :native.
2. waf tries performing a native build, because the relevant environment
   variables are not set up. One should set CC and PKGCONFIG (not
   the usual PKG_CONFIG) for tevent.
3. waf tries running a simple hello world program.
4. waf performs sizeof checks by running programs.
5. waf has a mandatory run test for determining whether mkstemp works.
6. probably more

The attached patch fixes 1-4. I don't know a good solution for 5. As
such it is an incremental step towards cross building tevent. Please
consider applying it and close this bug when doing so.

Helmut
-------------- next part --------------
diff --minimal -Nru tevent-0.9.39/debian/changelog tevent-0.9.39/debian/changelog
--- tevent-0.9.39/debian/changelog	2019-08-29 14:43:48.000000000 +0200
+++ tevent-0.9.39/debian/changelog	2019-09-06 21:41:32.000000000 +0200
@@ -1,3 +1,14 @@
+tevent (0.9.39-2.1) UNRELEASED; urgency=medium
+
+  * Non-maintainer upload.
+  * Improve cross building. (Closes: #-1)
+    + Annotate the python3 Build-Depends with :any.
+    + Export CC and PKGCONFIG for waf.
+    + cross.patch: don't run an unnecessary hello world test
+    + cross.patch: use compile-only checks for sizeof validation
+
+ -- Helmut Grohne <helmut at subdivi.de>  Fri, 06 Sep 2019 21:41:32 +0200
+
 tevent (0.9.39-2) unstable; urgency=medium
 
   * Upload to unstable
diff --minimal -Nru tevent-0.9.39/debian/control tevent-0.9.39/debian/control
--- tevent-0.9.39/debian/control	2019-08-29 14:05:41.000000000 +0200
+++ tevent-0.9.39/debian/control	2019-09-06 21:41:30.000000000 +0200
@@ -7,7 +7,7 @@
                libaio-dev [linux-any],
                libtalloc-dev (>= 2.1.16~),
                pkg-config,
-               python3
+               python3:any
 Rules-Requires-Root: no
 Standards-Version: 4.4.0
 Homepage: https://tevent.samba.org/
diff --minimal -Nru tevent-0.9.39/debian/patches/cross.patch tevent-0.9.39/debian/patches/cross.patch
--- tevent-0.9.39/debian/patches/cross.patch	1970-01-01 01:00:00.000000000 +0100
+++ tevent-0.9.39/debian/patches/cross.patch	2019-09-06 21:41:32.000000000 +0200
@@ -0,0 +1,55 @@
+--- tevent-0.9.39.orig/buildtools/wafsamba/wscript
++++ tevent-0.9.39/buildtools/wafsamba/wscript
+@@ -298,7 +298,7 @@
+     conf.CHECK_CODE('printf("hello world")',
+                     define='HAVE_SIMPLE_C_PROG',
+                     mandatory=True,
+-                    execute=True,
++                    execute=False,
+                     headers='stdio.h',
+                     msg='Checking simple C program')
+ 
+--- tevent-0.9.39.orig/buildtools/wafsamba/samba_conftests.py
++++ tevent-0.9.39/buildtools/wafsamba/samba_conftests.py
+@@ -86,9 +86,9 @@
+     '''see what we need for largefile support'''
+     getconf_cflags = conf.CHECK_COMMAND(['getconf', 'LFS_CFLAGS']);
+     if getconf_cflags is not False:
+-        if (conf.CHECK_CODE('if (sizeof(off_t) < 8) return 1',
++        if (conf.CHECK_CODE('char dummy[(sizeof(off_t) < 8) ? -1 : 1',
+                             define='WORKING_GETCONF_LFS_CFLAGS',
+-                            execute=True,
++                            execute=False,
+                             cflags=getconf_cflags,
+                             msg='Checking getconf large file support flags work')):
+             conf.ADD_CFLAGS(getconf_cflags)
+@@ -101,23 +101,23 @@
+                     else:
+                         conf.DEFINE(flag_split[0], flag_split[1])
+ 
+-    if conf.CHECK_CODE('if (sizeof(off_t) < 8) return 1',
++    if conf.CHECK_CODE('char dummy[(sizeof(off_t) < 8) ? -1 : 1',
+                        define,
+-                       execute=True,
++                       execute=False,
+                        msg='Checking for large file support without additional flags'):
+         return True
+ 
+-    if conf.CHECK_CODE('if (sizeof(off_t) < 8) return 1',
++    if conf.CHECK_CODE('char dummy[(sizeof(off_t) < 8) ? -1 : 1]',
+                        define,
+-                       execute=True,
++                       execute=False,
+                        cflags='-D_FILE_OFFSET_BITS=64',
+                        msg='Checking for -D_FILE_OFFSET_BITS=64'):
+         conf.DEFINE('_FILE_OFFSET_BITS', 64)
+         return True
+ 
+-    if conf.CHECK_CODE('if (sizeof(off_t) < 8) return 1',
++    if conf.CHECK_CODE('char dummy[(sizeof(off_t) < 8) ? -1 : 1]',
+                        define,
+-                       execute=True,
++                       execute=False,
+                        cflags='-D_LARGE_FILES',
+                        msg='Checking for -D_LARGE_FILES'):
+         conf.DEFINE('_LARGE_FILES', 1)
diff --minimal -Nru tevent-0.9.39/debian/patches/series tevent-0.9.39/debian/patches/series
--- tevent-0.9.39/debian/patches/series	1970-01-01 01:00:00.000000000 +0100
+++ tevent-0.9.39/debian/patches/series	2019-09-06 21:41:32.000000000 +0200
@@ -0,0 +1 @@
+cross.patch
diff --minimal -Nru tevent-0.9.39/debian/rules tevent-0.9.39/debian/rules
--- tevent-0.9.39/debian/rules	2019-08-29 13:31:30.000000000 +0200
+++ tevent-0.9.39/debian/rules	2019-09-06 21:41:32.000000000 +0200
@@ -1,5 +1,10 @@
 #!/usr/bin/make -f
 
+-include /usr/share/dpkg/buildtools.mk
+export CC
+PKG_CONFIG ?= pkg-config
+export PKGCONFIG=${PKG_CONFIG}
+
 CFLAGS = -g -Wall
 
 ifneq (,$(findstring noopt,$(DEB_BUILD_OPTIONS)))