From cc58ce6a74c1ec4bac862d2aa879153a6b6d30df Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@efficios.com>
Date: Fri, 24 Apr 2020 11:46:39 -0400
Subject: [PATCH] gthread: ignore deprecated declarations in static inline
 functions
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With a trivial file that just includes glib.h:

    #include <glib.h>

Compiled with:

    gcc -c test.c \
      -I /tmp/glib/include/glib-2.0/ \
      -I /tmp/glib/lib/x86_64-linux-gnu/glib-2.0/include \
      -DGLIB_VERSION_MAX_ALLOWED=GLIB_VERSION_2_28 \
      -DGLIB_VERSION_MIN_REQUIRED=GLIB_VERSION_2_28 \
      -fmax-errors=1 \
      -Werror

We get:

    In file included from /tmp/glib/include/glib-2.0/glib/gasyncqueue.h:32,
                     from /tmp/glib/include/glib-2.0/glib.h:32,
                     from test.c:1:
    /tmp/glib/include/glib-2.0/glib/gthread.h: In function ‘g_rec_mutex_locker_new’:
    /tmp/glib/include/glib-2.0/glib/gthread.h:396:3: error: ‘g_rec_mutex_lock’ is deprecated: Not available before 2.32 [-Werror=deprecated-declarations]
      396 |   g_rec_mutex_lock (rec_mutex);
          |   ^~~~~~~~~~~~~~~~
    /tmp/glib/include/glib-2.0/glib/gthread.h:196:17: note: declared here
      196 | void            g_rec_mutex_lock                (GRecMutex      *rec_mutex);
          |                 ^~~~~~~~~~~~~~~~
    compilation terminated due to -fmax-errors=1.

The problem is that the code in the static inline functions uses
g_rec_mutex_lock, introduced after 2.28.  This code is compiled
regardless of if it's actually used or not.

Suppress the warning by using G_GNUC_BEGIN_IGNORE_DEPRECATIONS /
G_GNUC_END_IGNORE_DEPRECATIONS.  There are precedents for doing that,
for example g_main_context_pusher_new in gmain.h.

Tested by building with all variations of GLIB_VERSION_MIN_REQUIRED /
GLIB_VERSION_MAX_ALLOWED:

    for i in $(seq 26 2 64); do
      gcc -c test.c \
        -I/tmp/glib/include/glib-2.0 \
        -I/tmp/glib/lib/x86_64-linux-gnu/glib-2.0/include \
        -DGLIB_VERSION_MAX_ALLOWED=GLIB_VERSION_2_$i \
        -DGLIB_VERSION_MIN_REQUIRED=GLIB_VERSION_2_$i \
        -fmax-errors=1 \
        -Werror
    done

Fixes: #2094
---
 glib/gthread.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/glib/gthread.h b/glib/gthread.h
index a8c7ac777..980522bba 100644
--- a/glib/gthread.h
+++ b/glib/gthread.h
@@ -390,12 +390,14 @@ typedef void GRecMutexLocker;
  * Returns: a #GRecMutexLocker
  * Since: 2.60
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline GRecMutexLocker *
 g_rec_mutex_locker_new (GRecMutex *rec_mutex)
 {
   g_rec_mutex_lock (rec_mutex);
   return (GRecMutexLocker *) rec_mutex;
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 /**
  * g_rec_mutex_locker_free:
@@ -407,11 +409,13 @@ g_rec_mutex_locker_new (GRecMutex *rec_mutex)
  *
  * Since: 2.60
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline void
 g_rec_mutex_locker_free (GRecMutexLocker *locker)
 {
   g_rec_mutex_unlock ((GRecMutex *) locker);
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 /**
  * GRWLockWriterLocker:
@@ -494,12 +498,14 @@ typedef void GRWLockWriterLocker;
  * Returns: a #GRWLockWriterLocker
  * Since: 2.62
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline GRWLockWriterLocker *
 g_rw_lock_writer_locker_new (GRWLock *rw_lock)
 {
   g_rw_lock_writer_lock (rw_lock);
   return (GRWLockWriterLocker *) rw_lock;
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 /**
  * g_rw_lock_writer_locker_free:
@@ -512,11 +518,13 @@ g_rw_lock_writer_locker_new (GRWLock *rw_lock)
  *
  * Since: 2.62
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline void
 g_rw_lock_writer_locker_free (GRWLockWriterLocker *locker)
 {
   g_rw_lock_writer_unlock ((GRWLock *) locker);
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 /**
  * GRWLockReaderLocker:
@@ -543,12 +551,14 @@ typedef void GRWLockReaderLocker;
  * Returns: a #GRWLockReaderLocker
  * Since: 2.62
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline GRWLockReaderLocker *
 g_rw_lock_reader_locker_new (GRWLock *rw_lock)
 {
   g_rw_lock_reader_lock (rw_lock);
   return (GRWLockReaderLocker *) rw_lock;
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 /**
  * g_rw_lock_reader_locker_free:
@@ -561,11 +571,13 @@ g_rw_lock_reader_locker_new (GRWLock *rw_lock)
  *
  * Since: 2.62
  */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 static inline void
 g_rw_lock_reader_locker_free (GRWLockReaderLocker *locker)
 {
   g_rw_lock_reader_unlock ((GRWLock *) locker);
 }
+G_GNUC_END_IGNORE_DEPRECATIONS
 
 G_END_DECLS