Changes between Version 8 and Version 9 of TBR/UserManual/Using_C_Plus_Plus

Timestamp:

06/26/07 18:44:15 (17 years ago)

Author:

Rsg

Comment:

/* PowerPC Initialisation */

TBR/UserManual/Using_C_Plus_Plus

@@ -56 +56 @@
  * However, there is a problem here, in that '''eabi()''' ends up calling '''init()''' (actually, '''__init()''', we renamed to fix the problem described here) when it is still too early to initialize the C++ environment.
 
-  '''Note''' both details are of the 'seems to work' type. You won't notice anything if you don't call '''eabi()''' until you try to use an essential SYSV/EABI feature. Likewise, calling '''init()''' too early might not cause problems in many cases until one of your constructors uses an yet unavailable feature provided by RTEMS such as '''malloc()'''.
+'''Note''' both details are of the 'seems to work' type. You won't notice anything if you don't call '''eabi()''' until you try to use an essential SYSV/EABI feature. Likewise, calling '''init()''' too early might not cause problems in many cases until one of your constructors uses an yet unavailable feature provided by RTEMS such as '''malloc()'''.
 
 For the PowerPC a typical chicken and egg problem exists -
 
-##we want to call '''_eabi()''' early (libbsp/powerpc/shared/start/start.S)
-##we want to prevent '''_init()''' from being called too early (by '''eabi()''')
-##we want to call '''__init()''' at the apropriate time.
-##we dont want to hack gcc.
+#we want to call '''_eabi()''' early (libbsp/powerpc/shared/start/start.S)
+#we want to prevent '''_init()''' from being called too early (by '''eabi()''')
+#we want to call '''__init()''' at the apropriate time.
+#we dont want to hack gcc.
 
 Here's the solution using the '''.init''' magic as described in the appendix -
-  * an additional startup file '''rtems_crti.S''' terminates '''_init()'''
-  * so it becomes a no-op and introduces a new '''_init()''' entry point
-  * to be used by RTEMS ([wiki:ThreadHandler ThreadHandler]).
+ * an additional startup file '''rtems_crti.S''' terminates '''_init()'''
+ * so it becomes a no-op and introduces a new '''_init()''' entry point
+ * to be used by RTEMS ([wiki:ThreadHandler ThreadHandler]).
 
 Hence here's what you need :
-  * BSP's 'start.S' file must call '_eabi()'
-  * BSP's bsp_specs :
+ * BSP's 'start.S' file must call '_eabi()'
+ * BSP's bsp_specs :
 
     ''startfile'': must contain (order is crucial) :
@@ -94 +94 @@
 Here's what happens (properly linked executable) :
 
-##BSP '''start.s''' calls '''_eabi()'''; SYSVI/EABI environment setup
-##'''eabi()''' calls '''_init()'''
-##'''__init()''' returns immediately
-##BSP initializes
-##RTEMS starts up; initializes newlibc
-##[wiki:ThreadHandler ThreadHandler] calls '''''init()''' (points to what ''_init() was intended to do)
-##'''_init()''' walks through code snippets provided by various '''.init''' sections
-##'''''init()''' encounters '''''do''global''ctors_aux()''' (provided by '''crtend.o''')
-##'''''do''global''ctors''aux()''' initializes C++ environment (exceptions, ctors)
-##...
+#BSP '''start.s''' calls '''_eabi()'''; SYSVI/EABI environment setup
+#'''eabi()''' calls '''_init()'''
+#'''__init()''' returns immediately
+#BSP initializes
+#RTEMS starts up; initializes newlibc
+#[wiki:ThreadHandler ThreadHandler] calls '''''init()''' (points to what ''_init() was intended to do)
+#'''_init()''' walks through code snippets provided by various '''.init''' sections
+#'''''init()''' encounters '''''do''global''ctors_aux()''' (provided by '''crtend.o''')
+#'''''do''global''ctors''aux()''' initializes C++ environment (exceptions, ctors)
+#...
 = C++ .init Linker Magic =