Don't confuse suffixed hexadecimal with floating-point

1e30 is a floating-point constant, but 1e30h is not.  The scanner
won't know that until it sees the "h", so make sure we keep enough
state to be able to distinguish "1e30" (a possible hex constant) from
"1.e30", "1e+30" or "1.0" (unabiguously floating-point.)

1 files changed, 20 insertions, 3 deletions

diff --git a/stdscan.c b/stdscan.c
index 3979144..c2f97e8 100644
--- a/stdscan.c
+++ b/stdscan.c
@@ -118,6 +118,8 @@ int stdscan(void *private_data, struct tokenval *tv)
         bool rn_error;
 	bool is_hex = false;
 	bool is_float = false;
+	bool has_e = false;
+	bool has_h = false;
 	char c;
 
         r = stdscan_bufptr++;
@@ -128,8 +130,17 @@ int stdscan(void *private_data, struct tokenval *tv)
 	for (;;) {
 	    c = *stdscan_bufptr++;
 
-	    if ((!is_hex && (c == 'e' || c == 'E')) ||
-		(c == 'P' || c == 'p')) {
+	    if (!is_hex && (c == 'e' || c == 'E')) {
+		has_e = true;
+		if (*stdscan_bufptr == '+' || *stdscan_bufptr == '-') {
+		    /* e can only be followed by +/- if it is either a
+		       prefixed hex number or a floating-point number */
+		    is_float = true;
+		    stdscan_bufptr++;
+		}
+	    } else if (c == 'H' || c == 'h') {
+		has_h = true;
+	    } else if (c == 'P' || c == 'p') {
 		is_float = true;
 		if (*stdscan_bufptr == '+' || *stdscan_bufptr == '-')
 		    stdscan_bufptr++;
@@ -142,6 +153,11 @@ int stdscan(void *private_data, struct tokenval *tv)
 	}
 	stdscan_bufptr--;	/* Point to first character beyond number */
 
+	if (has_e && !has_h) {
+	    /* 1e13 is floating-point, but 1e13h is not */
+	    is_float = true;
+	}
+
 	if (is_float) {
 	    tv->t_charptr = stdscan_copy(r, stdscan_bufptr - r);
 	    return tv->t_type = TOKEN_FLOAT;
@@ -154,7 +170,8 @@ int stdscan(void *private_data, struct tokenval *tv)
 	    tv->t_charptr = NULL;
 	    return tv->t_type = TOKEN_NUM;
 	}
-    } else if (*stdscan_bufptr == '\'' || *stdscan_bufptr == '"') {     /* a char constant */
+    } else if (*stdscan_bufptr == '\'' || *stdscan_bufptr == '"') {
+	/* a char constant */
         char quote = *stdscan_bufptr++, *r;
         bool rn_warn;
         r = tv->t_charptr = stdscan_bufptr;