bitbake: build: print a backtrace with the original metadata locations of Bash shell funcs

Leverage the comments that emit_var writes and the backtrace that
the shell func writes to generate an additional metadata-relative
backtrace. This will help the user troubleshoot shell funcs much
more easily.

Example:

| WARNING: /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955:171 exit 1 from 'exit 1'
| WARNING: Backtrace (BB generated script):
| 	#1: myclass_do_something, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 171
| 	#2: do_something, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 166
| 	#3: actually_fail, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 153
| 	#4: my_compile_extra, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 155
| 	#5: do_compile, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 141
| 	#6: main, /home/laplante/repos/oe-core/build/tmp-glibc/work/core2-64-oe-linux/libsolv/0.7.14-r0/temp/run.do_compile.68955, line 184
|
| Backtrace (metadata-relative locations):
| 	#1: myclass_do_something, /home/laplante/repos/oe-core/meta/classes/myclass.bbclass, line 2
| 	#2: do_something, autogenerated, line 2
| 	#3: actually_fail, /home/laplante/repos/oe-core/meta/recipes-extended/libsolv/libsolv_0.7.14.bb, line 36
| 	#4: my_compile_extra, /home/laplante/repos/oe-core/meta/recipes-extended/libsolv/libsolv_0.7.14.bb, line 38
| 	#5: do_compile, autogenerated, line 3
ERROR: Task (/home/laplante/repos/oe-core/meta/recipes-extended/libsolv/libsolv_0.7.14.bb:do_compile) failed with exit code '1'
NOTE: Tasks Summary: Attempted 542 tasks of which 541 didn't need to be rerun and 1 failed.

Summary: 1 task failed:
  /home/laplante/repos/oe-core/meta/recipes-extended/libsolv/libsolv_0.7.14.bb:do_compile
Summary: There was 1 ERROR message shown, returning a non-zero exit code.

(Bitbake rev: ae1aa4ea79826c32b20e1e7abdf77a15b601c6f2)

Signed-off-by: Chris Laplante <chris.laplante@agilent.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/bitbake/lib/bb/process.py b/bitbake/lib/bb/process.py
index 2dc472a86f..f36c929d25 100644
--- a/bitbake/lib/bb/process.py
+++ b/bitbake/lib/bb/process.py
@@ -41,6 +41,7 @@ class ExecutionError(CmdError):
         self.exitcode = exitcode
         self.stdout = stdout
         self.stderr = stderr
+        self.extra_message = None
 
     def __str__(self):
         message = ""
@@ -51,7 +52,7 @@ class ExecutionError(CmdError):
         if message:
             message = ":\n" + message
         return (CmdError.__str__(self) +
-                " with exit code %s" % self.exitcode + message)
+                " with exit code %s" % self.exitcode + message + (self.extra_message or ""))
 
 class Popen(subprocess.Popen):
     defaults = {