[svn-r14056] Purpose: Take advantage of new H5_HAVE_SIGLONGJMP flag in H5detect.c

Description:
Visual Studio does not have the function siglongjmp.  Therefore, we have created a new configure flag H5_HAVE_SIGLONGJMP that tests for this.  We use this within H5detect.c.

Tested:
VS.NET
h5committest

release_docs/INSTALL_Windows.txt

@@ -1916,21 +1916,12 @@ To generate your own H5tinit.c, follow the steps below.
         
     1. Open the solution typegen.sln from the folder .\windows\misc\typgen.
         
-    2. Edit the code
-	
-	   Open the source file H5detect.c, and remove or comment the line:
-	   
-		siglongjmp(jbuf_g, 1);
-		
-	   This function is unsupported on Windows, and will cause Visual Studio
-	   2005 to crash.
-	   
-    3. Build H5tinit.exe
+    2. Build H5tinit.exe
     
         Make sure your configuration is set to Debug, and build the project.  
         This will generate H5tinit.exe in the .\src folder.
         
-    4. Create H5tinit.c
+    3. Create H5tinit.c
     
         From a command prompt, go to the .\src directory and issue the command:
             .\H5tinit.exe > H5tinit.c
@@ -1940,8 +1931,7 @@ To generate your own H5tinit.c, follow the steps below.
 Note:
 
     If you are building on 64-bit Windows, make sure you set your build
-    "Machine Type" to "X64".  Also, you will need to comment out any lines
-    referencing "siglongjmp", as this function is not present on 64-bit Windows.
+    "Machine Type" to "X64".
  
 ========================================================================
                             Section XIII: Misc.

src/H5detect.c

@@ -356,7 +356,7 @@ precision (detected_t *d)
     COMP_ALIGN = (size_t)((char*)(&(s.x)) - (char*)(&s));                     \
 }
 
-#if defined(H5_HAVE_LONGJMP) && defined(H5_HAVE_SIGNAL)
+#if defined(H5_HAVE_LONGJMP) && defined(H5_HAVE_SIGNAL) && defined(H5_HAVE_SIGLONGJMP)
 #define ALIGNMENT(TYPE,INFO) {						      \
     char		*volatile _buf=NULL;				      \
     volatile TYPE	_val=1;						      \