From: Keith Packard <keithp@keithp.com>
Date: Wed, 16 Nov 2016 22:12:59 +0000 (-0800)
Subject: altos/lisp: Eliminate compiler warning about array bounds at -O3
X-Git-Tag: 1.7~147
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=bcf5eb5825b1217d74f117b02d09b4ce4b007beb

altos/lisp: Eliminate compiler warning about array bounds at -O3

Using ao_lisp_pool - 4 caused the compiler to whinge about computing
an address outside the bounds of the array. Sigh. Restructure the code
to do the adjustment-by-4 in the integer computations instead of the
pointer ones.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/src/lisp/ao_lisp.h b/src/lisp/ao_lisp.h
index ea8d98b5..25d13fa3 100644
--- a/src/lisp/ao_lisp.h
+++ b/src/lisp/ao_lisp.h
@@ -118,9 +118,6 @@ ao_lisp_is_const(ao_poly poly) {
 	return poly & AO_LISP_CONST;
 }
 
-#define AO_LISP_POOL_BASE	(ao_lisp_pool - 4)
-#define AO_LISP_CONST_BASE	(ao_lisp_const - 4)
-
 #define AO_LISP_IS_CONST(a)	(ao_lisp_const <= ((uint8_t *) (a)) && ((uint8_t *) (a)) < ao_lisp_const + AO_LISP_POOL_CONST)
 #define AO_LISP_IS_POOL(a)	(ao_lisp_pool <= ((uint8_t *) (a)) && ((uint8_t *) (a)) < ao_lisp_pool + AO_LISP_POOL)
 
diff --git a/src/lisp/ao_lisp_mem.c b/src/lisp/ao_lisp_mem.c
index 53ebf757..12a5ba55 100644
--- a/src/lisp/ao_lisp_mem.c
+++ b/src/lisp/ao_lisp_mem.c
@@ -252,23 +252,6 @@ static inline uint16_t pool_offset(void *addr) {
 	return ((uint8_t *) addr) - ao_lisp_pool;
 }
 
-/*
- * Convert back and forth between 'poly's used
- * as short addresses in the pool and addresses.
- * These are used in the chunk code.
- */
-static inline ao_poly pool_poly(void *addr) {
-#if DBG_MEM
-	if (!AO_LISP_IS_POOL(addr))
-		ao_lisp_abort();
-#endif
-	return ((uint8_t *) addr) - AO_LISP_POOL_BASE;
-}
-
-static inline void *pool_ref(ao_poly p) {
-	return AO_LISP_POOL_BASE + p;
-}
-
 static inline void mark(uint8_t *tag, int offset) {
 	int	byte = offset >> 5;
 	int	bit = (offset >> 2) & 7;
diff --git a/src/lisp/ao_lisp_poly.c b/src/lisp/ao_lisp_poly.c
index 9717fd73..236176e7 100644
--- a/src/lisp/ao_lisp_poly.c
+++ b/src/lisp/ao_lisp_poly.c
@@ -89,8 +89,8 @@ ao_lisp_ref(ao_poly poly) {
 	if (poly == AO_LISP_NIL)
 		return NULL;
 	if (poly & AO_LISP_CONST)
-		return (void *) (AO_LISP_CONST_BASE + (poly & AO_LISP_REF_MASK));
-	return (void *) (AO_LISP_POOL_BASE + (poly & AO_LISP_REF_MASK));
+		return (void *) (ao_lisp_const + (poly & AO_LISP_REF_MASK) - 4);
+	return (void *) (ao_lisp_pool + (poly & AO_LISP_REF_MASK) - 4);
 }
 
 ao_poly
@@ -99,6 +99,6 @@ ao_lisp_poly(const void *addr, ao_poly type) {
 	if (a == NULL)
 		return AO_LISP_NIL;
 	if (AO_LISP_IS_CONST(a))
-		return AO_LISP_CONST | (a - AO_LISP_CONST_BASE) | type;
-	return (a - AO_LISP_POOL_BASE) | type;
+		return AO_LISP_CONST | (a - ao_lisp_const + 4) | type;
+	return (a - ao_lisp_pool + 4) | type;
 }
diff --git a/src/test/Makefile b/src/test/Makefile
index fae46ac8..0eaa9421 100644
--- a/src/test/Makefile
+++ b/src/test/Makefile
@@ -10,7 +10,7 @@ INCS=ao_kalman.h ao_ms5607.h ao_log.h ao_data.h altitude-pa.h altitude.h ao_quat
 
 KALMAN=make-kalman 
 
-CFLAGS=-I.. -I. -I../kernel -I../drivers -I../micropeak -I../product -I../lisp -O3 -g -Wall -DAO_LISP_TEST -no-pie
+CFLAGS=-I.. -I. -I../kernel -I../drivers -I../micropeak -I../product -I../lisp -O0 -g -Wall -DAO_LISP_TEST -no-pie
 
 all: $(PROGS) ao_aprs_data.wav