Red Hat ENTERPRISE LINUX 5.4 - SYSTEMTAP BEGINNERS GUIDE Manual page 62

Chapter 5. Understanding SystemTap Errors
semantic error: unresolved type for identifier 'foo'
The identifier (e.g. a variable) was used, but no type (integer or string) could be determined. This
occurs, for instance, if you use a variable in a printf statement while the script never assigns a
value to the variable.
semantic error: Expecting symbol or array index expression
SystemTap could not assign a value to a variable or to a location in an array. The destination for the
assignment is not a valid destination. The following example code would generate this error:
probe begin { printf("x") = 1 }
while searching for arity N function, semantic error: unresolved function call
A function call or array index expression in the script used an invalid number of arguments/
parameters. In SystemTap arity can either refer to the number of indices for an array, or the number of
parameters to a function.
semantic error: array locals not supported, missing global declaration?
The script used an array operation without declaring the array as a global variable (global variables
can be declared after their use in Systemtap scripts). Similar messages appear if an array is used, but
with inconsistent arities.
semantic error: variable 'foo' modified during 'foreach' iteration
The array foo is being modifed (being assigned to or deleted from) within an active foreach loop.
This error also displays if an operation within the script performs a function call within the foreach
loop.
semantic error: probe point mismatch at position N, while resolving probe point foo
SystemTap did not understand what the event or SystemTap function foo refers to. This usually
means that SystemTap could not find a match for foo in the tapset library. The N refers to the line and
column of the error.
semantic error: no match for probe point, while resolving probe point foo
The events / handler function foo could not be resolved altogether, for a variety of reasons. This error
occurs when the script contains the event kernel.function("blah"), and blah does not exist.
In some cases, the error could also mean the script contains an invalid kernel file name or source line
number.
semantic error: unresolved target-symbol expression
A handler in the script references a target variable, but the value of the variable could not be resolved.
This error could also mean that a handler is referencing a target variable that is not valid in the context
when it was referenced. This may be a result of compiler optimization of the generated code.
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