Specialize paths to version.h in _vxworks-versions.h

The _vxworks-versions.h runtime file helps us control
the compilation of some library components depending on
the OS version extracted out of a system header.

The system header name is "version.h", and gcc has a
"version.h" file of its own.

gcc's version.h is now generated and the current
instance instead of the OS one, resulting in build failures
from

  #if !defined(_WRS_VXWORKS_MAJOR)
  #error "_WRS_VXWORKS_MAJOR undefined"
  #endif

This change introduces a twist in the way
_vxworks-versions.h #includes version.h, using a relative
path with components that will match in the OS include
dirs only.

The actual relative path is conditioned on _VSB_CONFIG_FILE
to accommodate a change in the include dirs organisation between
VxWorks 6 and 7.

2022-10-07  Olivier Hainque  <hainque@adacore.com>

gcc/
	* config/vxworks/_vxworks-versions.h: Use OS specific
	paths in #include of version.h.

diff --git a/gcc/config/vxworks/_vxworks-versions.h b/gcc/config/vxworks/_vxworks-versions.h
index 15e8bfeb4a60c44b42532e272454eb56d6967d03..994dda906430b82c103f9aef5429f98ebd1c076a 100644 (file)
--- a/gcc/config/vxworks/_vxworks-versions.h
+++ b/gcc/config/vxworks/_vxworks-versions.h
@@ -23,15 +23,24 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #define _VXWORKS_VERSIONS_H  1
 
 /* All we need is access to the bare _WRS_VXWORKS_MAJOR/MINOR macros,
-   exposed by version.h or already provided somehow (e.g. with a self
-   spec for some reason).  When resorting to system headers, cheat a
-   bit to make sure we don't drag additional header files, which can
-   easily cause #include ordering nightmares.  */
+   exposed by version.h or already provided somehow (e.g. with a self spec
+   for some reason).  When resorting to system headers, use typical os
+   paths to prevent possible confusion with a gcc version of version.h
+   visible during the build and temporarily #undef _WRS_KERNEL to prevent
+   indirect inclusion of internal header files, which can easily cause
+   #include ordering nightmares.  */
 
 #if !defined(_WRS_VXWORKS_MAJOR)
+
+#if defined(_VSB_CONFIG_FILE)
+#define _VXWORKS_VERSION_H <../public/version.h>
+#else
+#define _VXWORKS_VERSION_H <../h/version.h>
+#endif
+
 #pragma push_macro("_WRS_KERNEL")
 #undef _WRS_KERNEL
-#include <version.h>
+#include _VXWORKS_VERSION_H
 #pragma pop_macro("_WRS_KERNEL")
 #endif