diff options
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/c-lex.c | 46 | ||||
| -rw-r--r-- | gcc/cp/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/cp/lex.c | 44 |
4 files changed, 63 insertions, 37 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 17a4ab6..efe62f9 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +Wed Jul 21 08:39:22 1999 Gavin Romig-Koch <gavin@cygnus.com> + + * c-lex.c (yylex) : Correct the test for overflow when lexing + integer literals. + Tue Jul 20 18:02:42 1999 Richard Henderson <rth@cygnus.com> * haifa-sched.c (insn_cost): FREE implies cost 0 and vice versa. diff --git a/gcc/c-lex.c b/gcc/c-lex.c index 252888d..52387f8 100644 --- a/gcc/c-lex.c +++ b/gcc/c-lex.c @@ -1477,16 +1477,19 @@ yylex () int count = 0; int largest_digit = 0; int numdigits = 0; - /* for multi-precision arithmetic, - we actually store only HOST_BITS_PER_CHAR bits in each part. - The number of parts is chosen so as to be sufficient to hold - the enough bits to fit into the two HOST_WIDE_INTs that contain - the integer value (this is always at least as many bits as are - in a target `long long' value, but may be wider). */ -#define TOTAL_PARTS ((HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR) * 2 + 2) - int parts[TOTAL_PARTS]; int overflow = 0; + /* We actually store only HOST_BITS_PER_CHAR bits in each part. + The code below which fills the parts array assumes that a host + int is at least twice as wide as a host char, and that + HOST_BITS_PER_WIDE_INT is an even multiple of HOST_BITS_PER_CHAR. + Two HOST_WIDE_INTs is the largest int literal we can store. + In order to detect overflow below, the number of parts (TOTAL_PARTS) + must be exactly the number of parts needed to hold the bits + of two HOST_WIDE_INTs. */ +#define TOTAL_PARTS ((HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR) * 2) + unsigned int parts[TOTAL_PARTS]; + enum anon1 { NOT_FLOAT, AFTER_POINT, TOO_MANY_POINTS, AFTER_EXPON} floatflag = NOT_FLOAT; @@ -1616,11 +1619,16 @@ yylex () else parts[0] += c; } - - /* If the extra highest-order part ever gets anything in it, - the number is certainly too big. */ - if (parts[TOTAL_PARTS - 1] != 0) - overflow = 1; + + /* If the highest-order part overflows (gets larger than + a host char will hold) then the whole number has + overflowed. Record this and truncate the highest-order + part. */ + if (parts[TOTAL_PARTS - 1] >> HOST_BITS_PER_CHAR) + { + overflow = 1; + parts[TOTAL_PARTS - 1] &= (1 << HOST_BITS_PER_CHAR) - 1; + } if (p >= token_buffer + maxtoken - 3) p = extend_token_buffer (p); @@ -1772,12 +1780,12 @@ yylex () c = GETC(); } - /* If it won't fit in the host's representation for integers, - then pedwarn. */ - - warn = overflow; - if (warn) - pedwarn ("integer constant is too large for this configuration of the compiler - truncated to %d bits", HOST_BITS_PER_WIDE_INT * 2); + /* If the literal overflowed, pedwarn about it now. */ + if (overflow) + { + warn = 1; + pedwarn ("integer constant is too large for this configuration of the compiler - truncated to %d bits", HOST_BITS_PER_WIDE_INT * 2); + } /* This is simplified by the fact that our constant is always positive. */ diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 7df7bab..d5d2fa1 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,8 @@ +1999-07-21 Gavin Romig-Koch <gavin@cygnus.com> + + * lex.c (real_yylex) : Correct the test for overflow when lexing + integer literals. + 1999-07-20 Jason Merrill <jason@yorick.cygnus.com> * decl.c (warn_extern_redeclared_static): Check DECL_ARTIFICIAL, diff --git a/gcc/cp/lex.c b/gcc/cp/lex.c index dd083fd..a656ac4 100644 --- a/gcc/cp/lex.c +++ b/gcc/cp/lex.c @@ -3578,16 +3578,19 @@ real_yylex () int count = 0; int largest_digit = 0; int numdigits = 0; - /* for multi-precision arithmetic, - we actually store only HOST_BITS_PER_CHAR bits in each part. - The number of parts is chosen so as to be sufficient to hold - the enough bits to fit into the two HOST_WIDE_INTs that contain - the integer value (this is always at least as many bits as are - in a target `long long' value, but may be wider). */ -#define TOTAL_PARTS ((HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR) * 2 + 2) - int parts[TOTAL_PARTS]; int overflow = 0; + /* We actually store only HOST_BITS_PER_CHAR bits in each part. + The code below which fills the parts array assumes that a host + int is at least twice as wide as a host char, and that + HOST_BITS_PER_WIDE_INT is an even multiple of HOST_BITS_PER_CHAR. + Two HOST_WIDE_INTs is the largest int literal we can store. + In order to detect overflow below, the number of parts (TOTAL_PARTS) + must be exactly the number of parts needed to hold the bits + of two HOST_WIDE_INTs. */ +#define TOTAL_PARTS ((HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR) * 2) + unsigned int parts[TOTAL_PARTS]; + enum anon1 { NOT_FLOAT, AFTER_POINT, TOO_MANY_POINTS} floatflag = NOT_FLOAT; @@ -3694,10 +3697,15 @@ real_yylex () parts[0] += c; } - /* If the extra highest-order part ever gets anything in it, - the number is certainly too big. */ - if (parts[TOTAL_PARTS - 1] != 0) - overflow = 1; + /* If the highest-order part overflows (gets larger than + a host char will hold) then the whole number has + overflowed. Record this and truncate the highest-order + part. */ + if (parts[TOTAL_PARTS - 1] >> HOST_BITS_PER_CHAR) + { + overflow = 1; + parts[TOTAL_PARTS - 1] &= (1 << HOST_BITS_PER_CHAR) - 1; + } if (p >= token_buffer + maxtoken - 3) p = extend_token_buffer (p); @@ -3850,12 +3858,12 @@ real_yylex () c = token_getch (); } - /* If it won't fit in the host's representation for integers, - then pedwarn. */ - - warn = overflow; - if (warn) - pedwarn ("integer constant is too large for this configuration of the compiler - truncated to %d bits", HOST_BITS_PER_WIDE_INT * 2); + /* If the literal overflowed, pedwarn about it now. */ + if (overflow) + { + warn = 1; + pedwarn ("integer constant is too large for this configuration of the compiler - truncated to %d bits", HOST_BITS_PER_WIDE_INT * 2); + } /* This is simplified by the fact that our constant is always positive. */ |