gw-basic-2026

evv/gw-basic-2026

Fork 0

Commit Graph

Author	SHA1	Message	Date
Eremey Valetov	20ecdae938	Add --warn and --safe memory safety flags to the compiler Three progressive levels for gwbasic-compile: --warn: static analysis warnings (uninitialized variables, GOTO to nonexistent line, unreachable code detection). Zero runtime cost. --safe (implies --warn): runtime checked integer arithmetic via gw_int_add/sub/mul/neg matching real GW-BASIC overflow semantics, enhanced array bounds diagnostics with variable names and line numbers, GOSUB stack overflow diagnostics with source line reporting. --safe=sanitize (implies --safe): passes -fsanitize=address,undefined to gcc for full memory error detection. Also: fix pre-existing missing closing paren in array LET-to-integer codegen, add strpool_pin/unpin infrastructure, add compiler optimization flags and memory safety sections to roadmap. 72/72 interpreter tests pass. 64/64 eligible compiler tests pass in --safe mode.	2026-04-09 13:14:26 -04:00
Eremey Valetov	eb32021c19	Implement string space pool with compacting garbage collector Replaces individual malloc/free string management with a contiguous pool (default 32KB) and compacting GC, matching the original GW-BASIC's GETSPA/GARBAG architecture. Allocation is a bump pointer; gw_str_free() is a no-op (descriptors are nulled, data reclaimed by GC). Compaction runs at statement boundaries when the pool drops below 4KB free, walking the variable table and array storage to relocate live strings. FRE() now returns actual free pool space. FRE("") triggers a GC pass before reporting. CLEAR n sets the string space size.	2026-03-29 04:55:48 -04:00

Author

SHA1

Message

Date

Eremey Valetov

20ecdae938

Add --warn and --safe memory safety flags to the compiler

Three progressive levels for gwbasic-compile:

--warn: static analysis warnings (uninitialized variables, GOTO to
nonexistent line, unreachable code detection). Zero runtime cost.

--safe (implies --warn): runtime checked integer arithmetic via
gw_int_add/sub/mul/neg matching real GW-BASIC overflow semantics,
enhanced array bounds diagnostics with variable names and line numbers,
GOSUB stack overflow diagnostics with source line reporting.

--safe=sanitize (implies --safe): passes -fsanitize=address,undefined
to gcc for full memory error detection.

Also: fix pre-existing missing closing paren in array LET-to-integer
codegen, add strpool_pin/unpin infrastructure, add compiler optimization
flags and memory safety sections to roadmap.

72/72 interpreter tests pass. 64/64 eligible compiler tests pass in
--safe mode.

2026-04-09 13:14:26 -04:00

Eremey Valetov

eb32021c19

Implement string space pool with compacting garbage collector

Replaces individual malloc/free string management with a contiguous pool
(default 32KB) and compacting GC, matching the original GW-BASIC's
GETSPA/GARBAG architecture. Allocation is a bump pointer; gw_str_free()
is a no-op (descriptors are nulled, data reclaimed by GC). Compaction
runs at statement boundaries when the pool drops below 4KB free, walking
the variable table and array storage to relocate live strings.

FRE() now returns actual free pool space. FRE("") triggers a GC pass
before reporting. CLEAR n sets the string space size.

2026-03-29 04:55:48 -04:00

2 Commits