ports/181584: x11/nvidia-driver NVIDIA-FreeBSD-x86_64-319.32 fails to build due to uninitialized data warning and -Werror flag

[Nathanael Hoyle]

>Number:         181584
>Category:       ports
>Synopsis:       x11/nvidia-driver NVIDIA-FreeBSD-x86_64-319.32 fails to build due to uninitialized data warning and -Werror flag
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Aug 27 14:20:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Nathanael Hoyle
>Release:        9.1-RELEASE
>Organization:
>Environment:
FreeBSD tsuba 9.1-RELEASE FreeBSD 9.1-RELEASE #0 r243825: Tue Dec  4 09:23:10 UTC 2012     root at farrell.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
Build fails with:

nvidia_acpi.c: In function 'nv_acpi_dsm_method':
nvidia_acpi.c:166: warning: 'data_size' may be used uninitialized in this function
*** [nvidia_acpi.o] Error code 1

note that this is a warning, but -Werror compiler flag is forced on (not present in make.conf).

Subsequent message recommends setting MAKE_JOBS_UNSAFE=yes, but this has no effect.
>How-To-Repeat:
Attempt to build x11/nvidia-driver from ports.
>Fix:
The first usage of the data_size variable appears to be on line 203, and it is used as an "out" argument to nvidia_acpi_extract_object. That function initializes it to 0 at the beginning (line 97), so the usage is not actually unsafe. Nevertheless, initializing it to 0 at the point of declaration should have no change in behavior and suppress this warning.

--- nvidia_acpi.c.orig  2013-08-27 10:11:43.149516389 -0400
+++ nvidia_acpi.c       2013-08-27 10:12:02.588515738 -0400
@@ -163,7 +163,7 @@
     union acpi_object *dsm;
     union acpi_object dsm_input[4];
     struct acpi_object_list input = { 4, dsm_input };
-    uint32_t data_size;
+    uint32_t data_size = 0;
 
     dev = device_get_parent(nv->handle);
 


>Release-Note:
>Audit-Trail:
>Unformatted: