Make headers compilable with g++ 4.7

bluez.spec

@@ -1,7 +1,7 @@
 Summary: Bluetooth utilities
 Name: bluez
 Version: 4.98
-Release: 2%{?dist}
+Release: 3%{?dist}
 License: GPLv2+
 Group: Applications/System
 URL: http://www.bluez.org/
@@ -22,6 +22,8 @@ Patch5: 0001-Add-sixaxis-cable-pairing-plugin.patch
 Patch6: 0001-systemd-install-systemd-unit-files.patch
 
 Patch7: sbc_mmx.patch
+# Bug #791292
+Patch8: cplusplus_void_cast.patch
 
 BuildRequires: flex
 BuildRequires: dbus-devel >= 0.90
@@ -147,6 +149,7 @@ and mouse.
 %patch5 -p1 -b .cable-pairing
 %patch6 -p1 -b .systemd
 %patch7 -p1 -b .mmx
+%patch8 -p1 -b .cplusplus
 
 %build
 libtoolize -f -c
@@ -311,6 +314,9 @@ fi
 %exclude /usr/lib/udev/rules.d/97-bluetooth-hid2hci.rules
 
 %changelog
+* Tue Feb 28 2012 Petr Pisar <ppisar@redhat.com> - 4.98-3
+- Make headers compilable with g++ 4.7 (bug #791292)
+
 * Fri Feb 24 2012 Peter Robinson <pbrobinson@fedoraproject.org> 4.98-2
 - Add mmx patch to fix build of sbc component
 - clean up spec, drop ancient obsoletes

cplusplus_void_cast.patch

@@ -0,0 +1,82 @@
+From 21c794102c27d8474809cb54578941f8bbe63218 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
+Date: Tue, 28 Feb 2012 11:22:11 +0100
+Subject: [PATCH] Fix compiling C++ applications
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+The compiler error is:
+ /usr/include/bluetooth/bluetooth.h::131:9: error: invalid conversion from 'void*' to 'bt_get_le64(void*)::<anonymous struct>*'
+ ...
+
+The reason is that C++, in contrast to C, does not allow conversion of
+void * to anything, and this code gets compiled as C++ when the app is
+written in C++. The macro with the assignment itself is older, but only
+recent Bluez starts to use it in inline functions, thus triggering the
+problem.
+
+This patch keeps the "struct __attribute__((packed))" magic and merely
+changes the typecast so that it works in C and C++. Like the existing
+macro this patch relies on support for typeof.
+
+The new variant of the code is in an ifdef and only used for C++
+to avoid unexpected regressions in C applications.
+
+Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
+---
+ lib/bluetooth.h |   31 +++++++++++++++++++++++++++++++
+ 1 files changed, 31 insertions(+), 0 deletions(-)
+
+diff --git a/lib/bluetooth.h b/lib/bluetooth.h
+index 5bd4f03..3f1a177 100644
+--- a/lib/bluetooth.h
++++ b/lib/bluetooth.h
+@@ -109,6 +109,12 @@ enum {
+ #endif
+ 
+ /* Bluetooth unaligned access */
++#ifndef __cplusplus
++/*
++ * traditional code, doesn't work in C++ because
++ * of the void * to struct pointer assignment
++ */
++
+ #define bt_get_unaligned(ptr)			\
+ ({						\
+ 	struct __attribute__((packed)) {	\
+@@ -125,6 +131,31 @@ do {						\
+ 	__p->__v = (val);			\
+ } while(0)
+ 
++#else /* __cplusplus */
++
++/*
++ * modified code with typeof typecast, for C++;
++ * the traditional code continues to be used for
++ * C to avoid unexpected regressions with this
++ * code here (it should work in C and C++, though)
++ */
++#define bt_get_unaligned(ptr)                  \
++({                                             \
++       struct __attribute__((packed)) {        \
++               typeof(*(ptr)) __v;             \
++       } *__p = (typeof(__p)) (ptr);           \
++       __p->__v;                               \
++})
++
++#define bt_put_unaligned(val, ptr)             \
++do {                                           \
++       struct __attribute__((packed)) {        \
++               typeof(*(ptr)) __v;             \
++       } *__p = (typeof(__p)) (ptr);           \
++       __p->__v = (val);                       \
++} while(0)
++#endif /* __cplusplus */
++
+ #if __BYTE_ORDER == __LITTLE_ENDIAN
+ static inline uint64_t bt_get_le64(void *ptr)
+ {
+-- 
+1.7.7.6
+