diff --git a/femtolisp/Makefile b/femtolisp/Makefile
index eb03b4e..98af21a 100644
--- a/femtolisp/Makefile
+++ b/femtolisp/Makefile
@@ -11,7 +11,7 @@ LLT = $(LLTDIR)/libllt.a
 
 # OS flags: LINUX, WIN32, MACOSX
 # architecture flags: __CPU__=xxx, BITS64, ARCH_X86, ARCH_X86_64
-CONFIG = -DLINUX -DARCH_X86 -D__CPU__=586
+CONFIG = -DLINUX -DARCH_X86_64 -DBITS64 -D__CPU__=686
 FLAGS = -falign-functions -Wall -Wno-strict-aliasing -I$(LLTDIR) $(CFLAGS) -DUSE_COMPUTED_GOTO $(CONFIG)
 LIBFILES = $(LLT)
 LIBS = $(LIBFILES) -lm
diff --git a/femtolisp/read.c b/femtolisp/read.c
index e3aae72..8b08dc0 100644
--- a/femtolisp/read.c
+++ b/femtolisp/read.c
@@ -60,11 +60,17 @@ int isnumtok_base(char *tok, value_t *pval, int base)
             if (pval) *pval = mk_double(D_NINF);
             return 1;
         }
+        errno = 0;
         i64 = strtoll(tok, &end, base);
+        if (errno)
+            return 0;
         if (pval) *pval = return_from_int64(i64);
         return (*end == '\0');
     }
+    errno = 0;
     ui64 = strtoull(tok, &end, base);
+    if (errno)
+        return 0;
     if (pval) *pval = return_from_uint64(ui64);
     return (*end == '\0');
 }
diff --git a/llt/Makefile b/llt/Makefile
index 49aabbe..4ff895a 100644
--- a/llt/Makefile
+++ b/llt/Makefile
@@ -12,7 +12,7 @@ TESTER = llttest
 
 # OS flags: LINUX, WIN32, MACOSX
 # architecture flags: __CPU__=xxx, BITS64, ARCH_X86, ARCH_X86_64
-CONFIG = -DLINUX -DARCH_X86 -D__CPU__=586
+CONFIG = -DLINUX -DARCH_X86_64 -DBITS64 -D__CPU__=686
 FLAGS = -Wall -Wno-strict-aliasing $(CFLAGS) $(CONFIG)
 LIBS =
 
diff --git a/llt/dtypes.h b/llt/dtypes.h
index 713802b..c38f6ca 100644
--- a/llt/dtypes.h
+++ b/llt/dtypes.h
@@ -156,7 +156,7 @@ typedef u_ptrint_t uptrint_t;
 #define BIT31      0x80000000
 
 #define DBL_EPSILON      2.2204460492503131e-16
-#define FLT_EPSILON      1.1920928e-7
+#define FLT_EPSILON      1.192092896e-7
 #define DBL_MAX          1.7976931348623157e+308
 #define DBL_MIN          2.2250738585072014e-308
 #define FLT_MAX          3.402823466e+38
diff --git a/llt/fp.c b/llt/fp.c
index 12731fc..a48ecd7 100644
--- a/llt/fp.c
+++ b/llt/fp.c
@@ -47,7 +47,6 @@ static inline int64_t llabs(int64_t j)
     return NBABS(j, 64);
 }
 #else
-extern int64_t llabs(int64_t j);
 #endif
 
 int dbl_equals(double a, double b)