Group:
memory management
Topic:
aliasing
Topic:
memory management by garbage collection
Topic:
pointer rotation
Topic:
pointers to data
Topic:
safe use of pointers
| |
Summary
If an object has multiple references, deallocation may be difficult. Deallocation by use counts is error prone and adds a fixed overhead to each object. Garbage collection acts only when memory allocation fails, but it is often a slow process. Hardware tombstones left with dead objects provide automatic nullification of all referencing pointers. (cbb 5/80)
Subtopic: dangling pointers 
| Quote: with explicit storage allocation, programmer must avoid dangling references and storage leaks [»swinDC7_1985]
| | Quote: invalid pointers with explicit storage allocation from not initializing, bad arithmetic, type coercions [»swinDC7_1985]
| | Quote: replacement through invalid pointers can cause difficult-to-resolve overwrites
| | Quote: dangling pointers and storage leaks tend to persist long after other errors are removed; prevent with garbage collection [»nelsG_1991]
| | Quote: referential integrity if every foreign key refers to a primary key unless marked as a missing values [»coddEF_1990]
| | Quote: prevent dereferencing a deallocated heap pointer by replacing malloc with a garbage collector [»necuGC5_2005]
|
Subtopic: alias burying
| Quote: use alias burying to avoid destructive reads of 'read-once' variables; aliases must be dead when reading a unique field of possibly shared objects; static enforcement by restricting aliases across procedure calls [»boylJ5_2001]
|
Subtopic: tombstone
| Quote: leave a tombstone after deleting a data structure to invalidate pointers [»lomeDB1_1985]
| | Quote: catch dangling references by leaving a tombstone after the object is destroyed; needs hardware assistance [»lomeDB1_1975]
| | Quote: implement tombstones by indirect addressing for all pointers; then an invalid address will be caught by hardware [»lomeDB1_1985]
|
Subtopic: pointer scope
| Quote: associate scope with a pointer to avoid dangling pointers [»lomeDB1_1985]
| | Quote: assign pointer scope and the freeze all data structures until the scope terminates; an explicit free then has a delayed effect [»lomeDB1_1985]
|
Subtopic: two-way pointers
Quote: some frame languages use two-way pointers to update inverse relations; avoids tangling pointers by automatically updating all references
[»tichWF11_1987]
|
Related Topics
Group: memory management (11 topics, 367 quotes)
Topic: aliasing (28 items)
Topic: memory management by garbage collection (116 items)
Topic: pointer rotation (11 items)
Topic: pointers to data (55 items)
Topic: safe use of pointers
(102 items)
|
