From 0280407fc54f9b6225139c5ac27326f98f0cf043 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Fri, 3 Jul 2020 13:02:41 -0300
Subject: [PATCH] Details

Comments in makefile and function 'l_str2d'.
---
 lobject.c | 21 +++++++++++++--------
 makefile  | 19 ++++++++++---------
 2 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/lobject.c b/lobject.c
index 223bbd0c..f8ea917a 100644
--- a/lobject.c
+++ b/lobject.c
@@ -220,32 +220,37 @@ static lua_Number lua_strx2number (const char *s, char **endptr) {
 #define L_MAXLENNUM	200
 #endif
 
+/*
+** Convert string 's' to a Lua number (put in 'result'). Return NULL on
+** fail or the address of the ending '\0' on success. ('mode' == 'x')
+** means a hexadecimal numeral.
+*/
 static const char *l_str2dloc (const char *s, lua_Number *result, int mode) {
   char *endptr;
   *result = (mode == 'x') ? lua_strx2number(s, &endptr)  /* try to convert */
                           : lua_str2number(s, &endptr);
   if (endptr == s) return NULL;  /* nothing recognized? */
   while (lisspace(cast_uchar(*endptr))) endptr++;  /* skip trailing spaces */
-  return (*endptr == '\0') ? endptr : NULL;  /* OK if no trailing characters */
+  return (*endptr == '\0') ? endptr : NULL;  /* OK iff no trailing chars */
 }
 
 
 /*
-** Convert string 's' to a Lua number (put in 'result'). Return NULL
-** on fail or the address of the ending '\0' on success.
-** 'pmode' points to (and 'mode' contains) special things in the string:
-** - 'x'/'X' means a hexadecimal numeral
-** - 'n'/'N' means 'inf' or 'nan' (which should be rejected)
-** - '.' just optimizes the search for the common case (nothing special)
+** Convert string 's' to a Lua number (put in 'result') handling the
+** current locale.
 ** This function accepts both the current locale or a dot as the radix
 ** mark. If the conversion fails, it may mean number has a dot but
 ** locale accepts something else. In that case, the code copies 's'
 ** to a buffer (because 's' is read-only), changes the dot to the
 ** current locale radix mark, and tries to convert again.
+** The variable 'mode' checks for special characters in the string:
+** - 'n' means 'inf' or 'nan' (which should be rejected)
+** - 'x' means a hexadecimal numeral
+** - '.' just optimizes the search for the common case (no special chars)
 */
 static const char *l_str2d (const char *s, lua_Number *result) {
   const char *endptr;
-  const char *pmode = strpbrk(s, ".xXnN");
+  const char *pmode = strpbrk(s, ".xXnN");  /* look for special chars */
   int mode = pmode ? ltolower(cast_uchar(*pmode)) : 0;
   if (mode == 'n')  /* reject 'inf' and 'nan' */
     return NULL;
diff --git a/makefile b/makefile
index 9be23925..baa6e673 100644
--- a/makefile
+++ b/makefile
@@ -37,10 +37,15 @@ CWARNSC= -Wdeclaration-after-statement \
 
 CWARNS= $(CWARNSCPP) $(CWARNSC)
 
+# Some useful compiler options for internal tests:
+# -DHARDSTACKTESTS forces a reallocation of the stack at every point where
+# the stack can be reallocated.
+# -DHARDMEMTESTS forces an emergency collection at every single allocation.
+# -DEXTERNMEMCHECK removes internal consistency checking of blocks being
+# deallocated (useful when an external tool like valgrind does the check).
+# -DMAXINDEXRK=k limits range of constants in RK instruction operands.
+# -DLUA_COMPAT_5_3
 
-# -DEXTERNMEMCHECK -DHARDSTACKTESTS -DHARDMEMTESTS -DTRACEMEM='"tempmem"'
-# -DMAXINDEXRK=1 -DLUA_COMPAT_5_3
-# -g -DLUA_USER_H='"ltests.h"'
 # -pg -malign-double
 # -DLUA_USE_CTYPE -DLUA_USE_APICHECK
 # ('-ftrapv' for runtime checks of integer overflows)
@@ -81,11 +86,9 @@ LIB_O=	lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o lstrlib.o \
 LUA_T=	lua
 LUA_O=	lua.o
 
-# LUAC_T=	luac
-# LUAC_O=	luac.o print.o
 
-ALL_T= $(CORE_T) $(LUA_T) $(LUAC_T)
-ALL_O= $(CORE_O) $(LUA_O) $(LUAC_O) $(AUX_O) $(LIB_O)
+ALL_T= $(CORE_T) $(LUA_T)
+ALL_O= $(CORE_O) $(LUA_O) $(AUX_O) $(LIB_O)
 ALL_A= $(CORE_T)
 
 all:	$(ALL_T)
@@ -102,8 +105,6 @@ $(CORE_T): $(CORE_O) $(AUX_O) $(LIB_O)
 $(LUA_T): $(LUA_O) $(CORE_T)
 	$(CC) -o $@ $(MYLDFLAGS) $(LUA_O) $(CORE_T) $(LIBS) $(MYLIBS) $(DL)
 
-$(LUAC_T): $(LUAC_O) $(CORE_T)
-	$(CC) -o $@ $(MYLDFLAGS) $(LUAC_O) $(CORE_T) $(LIBS) $(MYLIBS)
 
 llex.o:
 	$(CC) $(CFLAGS) -Os -c llex.c