Add lvalue checking for IL function and FB invocations.

Fix comment.

Add clarifying comment.

Remove access to NULL pointer.

Make temporary fix to is_complex() method.

Fix comment. (thanks go to Manuele for pointing it put).

Stop lvalue checks after finding an error in the expression.

Remove erroneous check for S1 and R1, and add missing declrataion.

Start implement lvalue check in IL instruction.

Add lvalue check on fb invocation.

Literals are also part of expressions!

Implement check_assignment_to_expression in lvalue_check_c class.

Remove potential access to NULL pointer.

Start having nicer stage 4 error messages.

Improve usability command line under windows.

Ignore trailing EOLs when determining symbol location.
(Makes for niver error messages)

Add comment.

Fix Segmentation fault in check_assignment_to_output lvalue method.

Remove deprecated status for ANYTIME operations.

Produce similar error messages in stage2 and stage3.

Fix bug when handling code with data type errors.

Fix printing of data type errors in while and repeat statements.

Add lvalue check for non formal function invocations.

Fixing check for assingment to FOR control variables.

Moving get_var_name_c into its own file.

Fixing check for assignment to output variables.

Fixing some bugs in lvalue checking (other bugs remain - to be fixed later)

Add lvalue check class.

Determine the modifiers (CONST, REATAIN) used when declaring a variable.

Fix typo in comparison expression.

Removing code from search_varfb_instance_type_c (use search_var_instance_decl_c instead).
(Preparing to delete search_varfb_instance_type_c in the future!)

Fix bug by expanding permissible data input of search_var_instance_decl_c
(this will also prepare us for removing search_varfb_instance_type_c in the future)

Edit formating and delete unused code.

Start data type checking of var declarations (including direct variables!)

Delete incorrect comments I had inserted previously (confusing EQ and NE functions)

merging with Lauren't changeset.

merge with Laurent's changeset (essentially ignore all changes).

merge with Laurent's changeset (essentially, ignore all changes).

merging with Laurent's changes.

merging with Laurent's change.

merging with Laurent's revision 55b074ea7255 (essentially ignoring all changes)

Add coment warning about incorrect implementation of the NE standard function.

merging with Laurent's patch.

Print correct error message when handling IL function calls.

Edit error message.

Add EXPT widen table.

Some stupid code cleanups.

Some code cleanups.

Clean up the code.

Fix error messages of il function calls - it now prints out location info of first parameter.

Clean code for printing errors in expressions.

Clean code for comparison operations & operators.

Cleaning up XORN, ANDN, and ORN operator code.

Cleaning up some code.

Add 'widen' tables for AND, OR and XOR operations.

Add MOD widening table, and some code clean-ups.

Re-organizing the code.

Change setting of deprecated_operation from fill to narrow_candidate_datatypes_c.
Expand widening tables for ADD, SUB, MUL and DIV.

Clarify some details in the comments.

Add check widening status for IL operator.
Fix check widening status for ST expression.