pthreads: Fix CMake/Autotools to check for them

AcademySoftwareFoundation · May 4, 2020 · af8864d · af8864d
1 parent 2ef3d62
commit af8864d
Show file tree

Hide file tree

Showing 2 changed files with 46 additions and 21 deletions.
diff --git a/IlmBase/config/CMakeLists.txt b/IlmBase/config/CMakeLists.txt
@@ -29,8 +29,12 @@ if(Threads_FOUND)
 
   # we have threads, but do we have posix semaphores for sem_init?
   # should be in pthreads
-  if(NOT (APPLE OR WIN32))
-    check_include_files(semaphore.h ILMBASE_HAVE_SEMAPHORE_H)
+  if(NOT (APPLE OR (WIN32 AND (NOT MINGW))))
+    if(MINGW)
+      check_include_files("pthread_unistd.h;semaphore.h" ILMBASE_HAVE_SEMAPHORE_H)
+    else()
+      check_include_files(semaphore.h ILMBASE_HAVE_SEMAPHORE_H)
+    endif()
     if(ILMBASE_HAVE_SEMAPHORE_H AND ILMBASE_HAVE_PTHREAD)
       # should just be in libc, so no need for check_library_exists
       set(CMAKE_REQUIRED_FLAGS ${CMAKE_THREAD_LIBS_INIT})

diff --git a/IlmBase/m4/threads.m4 b/IlmBase/m4/threads.m4
@@ -258,25 +258,46 @@ if test "${enable_posix_sem:-yes}" != "no"; then
     AC_CHECK_HEADERS([semaphore.h], [
 	AC_SEARCH_LIBS(sem_init, [posix4 pthread], [
 	    AC_MSG_CHECKING([whether to use POSIX unnamed semaphores])
-	    AC_RUN_IFELSE([
-		AC_LANG_PROGRAM([#include <semaphore.h>], [
-		    sem_t mysem;
-		    if (sem_init (&mysem, 1, 1) == 0)
-		    {
-			if (sem_wait (&mysem) == 0)
-			{
-			    sem_post (&mysem);
-			    sem_destroy (&mysem);
-			    return 0;
-			}
-		    }
-		    return 1;
-		])
-		], [
-		AC_MSG_RESULT([yes])
-		am_posix_sem_ok=yes], [
-		AC_MSG_RESULT([no (pshared not usable)])], [
-		AC_MSG_RESULT([no (cannot check usability when cross compiling)])])
+		if test "${cross_compiling}" == "yes"; then
+			AC_LINK_IFELSE([
+			AC_LANG_PROGRAM([#include <semaphore.h>], [
+				sem_t mysem;
+				if (sem_init (&mysem, 1, 1) == 0)
+				{
+				if (sem_wait (&mysem) == 0)
+				{
+					sem_post (&mysem);
+					sem_destroy (&mysem);
+					return 0;
+				}
+				}
+				return 1;
+			])
+			], [
+			AC_MSG_RESULT([yes])
+			am_posix_sem_ok=yes], [
+			AC_MSG_RESULT([no (pshared not usable)])])
+		else
+			AC_RUN_IFELSE([
+			AC_LANG_PROGRAM([#include <semaphore.h>], [
+				sem_t mysem;
+				if (sem_init (&mysem, 1, 1) == 0)
+				{
+				if (sem_wait (&mysem) == 0)
+				{
+					sem_post (&mysem);
+					sem_destroy (&mysem);
+					return 0;
+				}
+				}
+				return 1;
+			])
+			], [
+			AC_MSG_RESULT([yes])
+			am_posix_sem_ok=yes], [
+			AC_MSG_RESULT([no (pshared not usable)])], [
+			AC_MSG_RESULT([no (we are cross-compiling, and this test should have only tried to link, not run.))])])
+			fi
 	])
     ])
 fi