* m4/features.m4:

        * m4/threads.m4:
          Updated several library checks to use a single call of my
          re/implementation of the new autoconf AC_SEARCH_LIBS test instead
          of having several AC_CHECK_LIB calls in a row.  Nice!

          The thread detection tests were overhauled.  They are now
          simpler but retain the same functionality as the previous
          tests.  They were greatly reduced in size so debugging, updating
          and enhancing should be much easier now.

        * m4/acinclude.m4:
          Reimplemented Autoconf's AC_SEARCH_LIBS into ACE_SEARCH_LIBS.
          The functionality is the same but the ACE reimplementation
          actually works when C++ is the test language.  For some reason
          Autoconf's test isn't being generated properly by GNU M4.

1 files changed, 105 insertions, 261 deletions

diff --git a/m4/threads.m4 b/m4/threads.m4
index 8ff7c239f60..7b9a7a6d3c0 100644
--- a/m4/threads.m4
+++ b/m4/threads.m4
@@ -46,194 +46,37 @@ dnl Check if compiler accepts specific flag to enable threads
       ])
    ],
    [
-    ace_cv_feature_thread_flag_set=no
-
-    ace_save_CXXFLAGS="$CXXFLAGS"
-    ace_save_CFLAGS="$CFLAGS"
-
-    CXXFLAGS="$CXXFLAGS -mt"
-    CFLAGS="$CFLAGS -mt"
-
-    ACE_CACHE_CHECK(if compiler can use -mt flag,
-      ace_cv_feature_has_mt_flag,
-      [
-       ACE_CHECK_THREAD_FLAGS(
-         [
-          ace_cv_feature_has_mt_flag=yes
-         ],
-         [
-          ace_cv_feature_has_mt_flag=no
-         ])
-      ],
-      [
-       ace_cv_feature_thread_flag_set=yes
-      ],
-      [
-       CXXFLAGS="$ace_save_CXXFLAGS"
-       CFLAGS="$ace_save_CFLAGS"
-      ])
-
-    if test "$ace_cv_feature_thread_flag_set" = no; then
- 
-      CXXFLAGS="$CXXFLAGS -pthread"
-      CFLAGS="$CFLAGS -pthread"
-
-      ACE_CACHE_CHECK(if compiler can use -pthread flag,
-        ace_cv_feature_has_pthread_flag,
-        [
-         ACE_CHECK_THREAD_FLAGS(
-           [
-            ace_cv_feature_has_pthread_flag=yes
-           ],
-           [
-            ace_cv_feature_has_pthread_flag=no
-           ])
-        ],
-        [
-         ace_cv_feature_thread_flag_set=yes
-        ],
-        [
-         CXXFLAGS="$ace_save_CXXFLAGS"
-         CFLAGS="$ace_save_CFLAGS"
-        ])
-
-    fi dnl test "$ace_cv_feature_thread_flag_set" = no
-
-    if test "$ace_cv_feature_thread_flag_set" = no; then
-
-      CXXFLAGS="$CXXFLAGS -pthreads"
-      CFLAGS="$CFLAGS -pthreads"
-
-      ACE_CACHE_CHECK(if compiler can use -pthreads flag,
-        ace_cv_feature_has_pthreads_flag,
-        [
-         ACE_CHECK_THREAD_FLAGS(
-           [
-            ace_cv_feature_has_pthreads_flag=yes
-           ],
-           [
-            ace_cv_feature_has_pthreads_flag=no
-           ])
-        ],
-        [
-         ace_cv_feature_thread_flag_set=yes
-        ],
-        [
-         CXXFLAGS="$ace_save_CXXFLAGS"
-         CFLAGS="$ace_save_CFLAGS"
-        ])
-
-    fi dnl test "$ace_cv_feature_thread_flag_set" = no
-
-    if test "$ace_cv_feature_thread_flag_set" = no; then
-
-      CXXFLAGS="$CXXFLAGS -mthreads"
-      CFLAGS="$CXXFLAGS -mthreads"
-
-      ACE_CACHE_CHECK(if compiler can use -mthreads flag,
-        ace_cv_feature_has_mthreads_flag,
-        [
-         ACE_CHECK_THREAD_FLAGS(
-           [
-            ace_cv_feature_has_mthreads_flag=yes
-           ],
-           [
-            ace_cv_feature_has_mthreads_flag=no
-           ])
-        ],
-        [
-         ace_cv_feature_thread_flag_set=yes
-        ],
-        [
-         CXXFLAGS="$ace_save_CXXFLAGS"
-         CFLAGS="$ace_save_CFLAGS"
-        ])
-
-    fi dnl test "$ace_cv_feature_thread_flag_set" = no
-
-    if test "$ace_cv_feature_thread_flag_set" = no; then
-
-      CXXFLAGS="$CXXFLAGS -threads"
-      CFLAGS="$CXXFLAGS -threads"
-
-      ACE_CACHE_CHECK(if compiler can use -threads flag,
-        ace_cv_feature_has_dash_threads_flag,
-        [
-         ACE_CHECK_THREAD_FLAGS(
-           [
-            ace_cv_feature_has_dash_threads_flag=yes
-           ],
-           [
-            ace_cv_feature_has_dash_threads_flag=no
-           ])
-        ],
-        [
-         ace_cv_feature_thread_flag_set=yes
-        ],
-        [
-         CXXFLAGS="$ace_save_CXXFLAGS"
-         CFLAGS="$ace_save_CFLAGS"
-        ])
-
-    fi dnl test "$ace_cv_feature_thread_flag_set" = no
-
-    if test "$ace_cv_feature_thread_flag_set" = no; then
-
-      CXXFLAGS="$CXXFLAGS -Kthread"
-      CFLAGS="$CXXFLAGS -Kthread"
-
-      ACE_CACHE_CHECK(if compiler can use -Kthread flag,
-        ace_cv_feature_has_kthread_flag,
-        [
-         ACE_CHECK_THREAD_FLAGS(
-           [
-            ace_cv_feature_has_kthread_flag=yes
-           ],
-           [
-            ace_cv_feature_has_kthread_flag=no
-           ])
-        ],
-        [
-         ace_cv_feature_thread_flag_set=yes
-        ],
-        [
-         CXXFLAGS="$ace_save_CXXFLAGS"
-         CFLAGS="$ace_save_CFLAGS"
-        ])
-
-    fi dnl test "$ace_cv_feature_thread_flag_set" = no
+    dnl The compiler/platform has no thread support linked in by default
+    dnl so search for a usable compiler flag to enable thread support.
+    dnl If no thread flag is found then the remaining tests should still
+    dnl figure out how to enable thread support via library checks.
+    ACE_SEARCH_THREAD_FLAGS(mt pthread pthreads mthreads threads Kthread,,)
    ],
    [
     dnl Do nothing
    ])
 
-dnl Check for UNIX International Threads -- STHREADS
-
-  ace_has_sthreads=no
-
-  AC_CHECK_FUNC(thr_create,
-    [
-     ace_has_sthreads=yes
-     AC_DEFINE(ACE_HAS_STHREADS)
-    ],
-    [
-     AC_CHECK_LIB(thread, thr_create, dnl
-                  [
-                   ace_has_sthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_STHREADS), the default behavior of
-dnl of adding "-lthread" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                   LIBS="$LIBS -lthread"
-                   AC_DEFINE(ACE_HAS_STHREADS)
-                  ],)
-    ])
-
-  dnl Sometimes thr_create is actually found with explicitly linking against
-  dnl -lthread, so try a more "exotic" function.
-  AC_CHECK_FUNC(rwlock_destroy, , AC_CHECK_LIB(thread, rwlock_destroy,,))dnl
+ dnl Check for UNIX International Threads -- STHREADS
+ ACE_SEARCH_LIBS(thr_create, thread,
+   [
+    ace_has_sthreads=yes
+    AC_DEFINE(ACE_HAS_STHREADS)
+   ],
+   [
+    ace_has_sthreads=no
+   ])
 
-dnl Check for POSIX threads
+ dnl Sometimes thr_create is actually found with explicitly linking against
+ dnl -lthread, so try a more "exotic" function.
+ ACE_SEARCH_LIBS(rwlock_destroy, thread,,)
 
+ dnl Check for POSIX threads
+ ACE_SEARCH_LIBS(pthread_create, pthread pthreads c_r gthreads,
+   [
+    ace_has_pthreads=yes
+    AC_DEFINE(ACE_HAS_PTHREADS)
+   ],
+   [
     dnl Check if platform provides pthreads backward compatibility macros
     dnl (Some platforms may define some pthread functions such as
     dnl  pthread_create() as macros when using a later implementation of
@@ -242,7 +85,7 @@ dnl Check for POSIX threads
     dnl  pthread_create() to co-exist with the old implementation of
     dnl  of pthread_create().)
 
-    AC_CACHE_CHECK(for pthreads backward compatibility macros,
+    ACE_CACHE_CHECK(for pthreads backward compatibility macros,
       ace_cv_lib_pthread_compat_macros,
       [
        AC_EGREP_CPP(ACE_PTHREAD_MACROS,
@@ -250,7 +93,7 @@ dnl Check for POSIX threads
 #include <pthread.h>
 
 #if defined (pthread_create)
-             ACE_PTHREAD_MACROS
+  ACE_PTHREAD_MACROS
 #endif
          ],
          [
@@ -259,89 +102,40 @@ dnl Check for POSIX threads
          [
           ace_cv_lib_pthread_compat_macros=no
          ])
-      ])
-
-    ace_has_pthreads=no
-
-dnl Check for POSIX threads -- PTHREADS
-    ACE_CHECK_FUNC(pthread_create, pthread.h,
+      ],
       [
-       ace_has_pthreads=yes
-       AC_DEFINE(ACE_HAS_PTHREADS)
+       dnl Check if pthread function names are mangled (e.g. DU 4.0)
+       dnl to maintain older Pthread Draft compatibility.
+       ACE_CHECK_FUNC(pthread_create, pthread.h,
+         [
+          ace_has_pthreads=yes
+          AC_DEFINE(ACE_HAS_PTHREADS)
+         ],
+         [
+          ACE_CHECK_LIB(pthread, pthread_create, pthread.h, dnl
+            [
+             ace_has_pthreads=yes
+             dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior
+             dnl of adding "-lpthread" to the "LIBS" variable no longer
+             dnl works, so we have to add it manually.
+             LIBS="$LIBS -lpthread"
+             AC_DEFINE(ACE_HAS_PTHREADS)
+            ],
+            [
+             ace_has_pthreads=yes
+            ])
+         ])
       ],
       [
-       AC_CHECK_LIB(pthread, pthread_create, dnl
-                    [
-                     ace_has_pthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior of
-dnl of adding "-lpthread" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                     LIBS="$LIBS -lpthread"
-                     AC_DEFINE(ACE_HAS_PTHREADS)
-                    ],)
-
-dnl Check if pthread function names are mangled (e.g. DU 4.0) to maintain
-dnl older Pthread Draft compatibility.
-       if test "$ace_has_pthreads" = no &&
-          test "$ace_cv_lib_pthread_compat_macros" = yes; then
-         ACE_CHECK_LIB(pthread, pthread_create, pthread.h, dnl
-                      [
-                       ace_has_pthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior of
-dnl of adding "-lpthread" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                       LIBS="$LIBS -lpthread"
-                       AC_DEFINE(ACE_HAS_PTHREADS)
-                      ],)
-       fi dnl test "$ace_has_pthreads" = no && have compatibilty macros
-
-dnl Check if we need to use -lpthreads instead (e.g. AIX 4.2)
-       if test "$ace_has_pthreads" = no; then
-         AC_CHECK_LIB(pthreads, pthread_create, dnl
-                      [
-                       ace_has_pthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior of
-dnl of adding "-lpthread" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                       LIBS="$LIBS -lpthreads"
-                       AC_DEFINE(ACE_HAS_PTHREADS)
-                      ],)
-       fi dnl test "$ace_has_pthreads" = no
-
-       if test "$ace_has_pthreads" = no; then  
-dnl Check for POSIX threads in -lc_r
-dnl Check if we already have the necessary library, first
-         AC_CHECK_LIB(c_r, pthread_create, dnl
-                      [
-                       ace_has_pthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior of
-dnl of adding "-lc_r" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                       LIBS="$LIBS -lc_r"
-                       AC_DEFINE(ACE_HAS_PTHREADS)
-                      ],)
-       fi dnl  test "$ace_has_pthreads" = no
-
-       if test "$ace_has_pthreads" = no; then  
-dnl Check for POSIX threads in -lgthreads, i.e. FSU Pthreads
-         AC_CHECK_LIB(gthreads, pthread_create, dnl
-                      [
-                       ace_has_pthreads=yes
-dnl Since we AC_DEFINE(ACE_HAS_PTHREADS), the default behavior of
-dnl of adding "-lgthreads" to the "LIBS" variable no longer works.
-dnl So, we have to add it manually.
-                       LIBS="$LIBS -lgthreads"
-                       AC_DEFINE(ACE_HAS_PTHREADS)
-                      ],)
-       fi dnl  test "$ace_has_pthreads" = no
+       ace_has_pthreads=no
       ])
+   ])
 
-dnl If we don't have any thread library, then disable threading altogether!
-  if test "$ace_has_pthreads" != yes && 
-     test "$ace_has_sthreads" != yes; then
-       ace_user_enable_threads=no
-  fi
-
+ dnl If we don't have any thread library, then disable threading altogether!
+ if test "$ace_has_pthreads" != yes && 
+    test "$ace_has_sthreads" != yes; then
+   ace_user_enable_threads=no
+ fi
 ])
 
 dnl This macro will check that the current compiler flags do something
@@ -413,3 +207,53 @@ $ace_real_function();
   ])
  ])
 ])
+
+dnl Check what compiler thread flag may be used, if any, from the given list.
+dnl The flag list is separated by white space.
+dnl Usage: ACE_SEARCH_THREAD_FLAGS(THREAD-FLAG-LIST,
+dnl                                [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+AC_DEFUN(ACE_SEARCH_THREAD_FLAGS, dnl
+[
+ ACE_CACHE_CHECK(for compiler thread flag,
+   ace_cv_thread_flag_search,
+   [
+    ace_save_CXXFLAGS="$CXXFLAGS"
+    ace_save_CFLAGS="$CFLAGS"
+
+    for i in $1; do
+      CXXFLAGS="$CXXFLAGS -$i"
+      CFLAGS="$CFLAGS -$i"
+
+      ACE_CHECK_THREAD_FLAGS(
+        [
+         ace_cv_thread_flag_search="-$i"
+
+         dnl A usable flag was found so break out of the loop.
+         break;
+        ],
+        [
+         ace_cv_thread_flag_search=no
+        ])
+
+      dnl Reset the flags for the next flag check.
+      CXXFLAGS="$ace_save_CXXFLAGS"
+      CFLAGS="$ace_save_CFLAGS"
+    done
+
+    dnl Reset the flags to a consistent state.
+    dnl This prevents duplicate flags from being added to
+    dnl the C/CXXFLAGS variable.
+    CXXFLAGS="$ace_save_CXXFLAGS"
+    CFLAGS="$ace_save_CFLAGS"
+   ],
+   [
+    dnl Add the found/cached thread flag to the C/CXXFLAGS variables
+    CXXFLAGS="$CXXFLAGS $ace_cv_thread_flag_search"
+    CFLAGS="$CFLAGS $ace_cv_thread_flag_search"
+
+    $2
+   ],
+   [
+    $3
+   ])
+])