ok : test1 1 ! ; ok : test2 1 test1 ; ok test2 Memory address not aligned ok ftrace ! Called from test1 at ffeacc5c test1 Called from test2 at ffeacc6a (ffe8b574) Called from (interpret at ffe8b6f8 execute Called from catch at ffe8a8ba ffefeff0 0 ffefebdc catch Called from (fload) at ffe8ced8 0 (fload) Called from interact at ffe8cf74 execute Called from catch at ffe8a8ba ffefefd4 0 ffefebdc catch Called from (quit at ffe8cf98
In this example, test2 calls test1, which tries to store a value to an unaligned address. This results in the exception: Memory address not aligned.
The first line of ftrace's output shows the last command that caused the exception to occur. The next lines show locations from which the subsequent commands were being called.
The last few lines are usually the same in any ftrace output, because that is the calling sequence in effect when the Forth interpreter interprets a word from the input stream.