[rt #111730] don't use I32 for offsets in vec()tonyc/vec64

do_vecset() do_vecget() used I32 for the offset, which meant that
offsets outside the -2Gb - +2Gb offset were truncated, resulting in
various misbehaviours.

size is still an I32 in each case, but that's limited to small numbers
- powers of 2 from 1 to a current maximum of 64, so I didn't see much
value to changing that.

4 files changed, 5 insertions, 7 deletions

diff --git a/doop.c b/doop.c
index f1304772c2..cac9e1a26b 100644
--- a/doop.c
+++ b/doop.c
@@ -760,7 +760,7 @@ Perl_do_sprintf(pTHX_ SV *sv, I32 len, SV **sarg)
 
 /* currently converts input to bytes if possible, but doesn't sweat failure */
 UV
-Perl_do_vecget(pTHX_ SV *sv, I32 offset, I32 size)
+Perl_do_vecget(pTHX_ SV *sv, SSize_t offset, I32 size)
 {
     dVAR;
     STRLEN srclen, len, uoffset, bitoffs = 0;
@@ -908,7 +908,7 @@ void
 Perl_do_vecset(pTHX_ SV *sv)
 {
     dVAR;
-    register I32 offset, bitoffs = 0;
+    register SSize_t offset, bitoffs = 0;
     register I32 size;
     register unsigned char *s;
     register UV lval;
diff --git a/embed.fnc b/embed.fnc
index 8e3527d5e4..a7f7dc3402 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -379,7 +379,7 @@ pR	|Off_t	|do_tell	|NN GV* gv
 : Defined in doop.c, used only in pp.c
 p	|I32	|do_trans	|NN SV* sv
 : Used in my.c and pp.c
-p	|UV	|do_vecget	|NN SV* sv|I32 offset|I32 size
+p	|UV	|do_vecget	|NN SV* sv|SSize_t offset|I32 size
 : Defined in doop.c, used only in mg.c (with /* XXX slurp this routine */)
 p	|void	|do_vecset	|NN SV* sv
 : Defined in doop.c, used only in pp.c
diff --git a/proto.h b/proto.h
index 781719be63..e43c4370ec 100644
--- a/proto.h
+++ b/proto.h
@@ -893,7 +893,7 @@ PERL_CALLCONV I32	Perl_do_trans(pTHX_ SV* sv)
 #define PERL_ARGS_ASSERT_DO_TRANS	\
 	assert(sv)
 
-PERL_CALLCONV UV	Perl_do_vecget(pTHX_ SV* sv, I32 offset, I32 size)
+PERL_CALLCONV UV	Perl_do_vecget(pTHX_ SV* sv, SSize_t offset, I32 size)
 			__attribute__nonnull__(pTHX_1);
 #define PERL_ARGS_ASSERT_DO_VECGET	\
 	assert(sv)
diff --git a/t/bigmem/vec.t b/t/bigmem/vec.t
index ccdbb9bc43..bf3c513f63 100644
--- a/t/bigmem/vec.t
+++ b/t/bigmem/vec.t
@@ -16,12 +16,11 @@ $Config{ptrsize} >= 8
 plan(7);
 
 # RT #111730: Negative offset to vec in lvalue context
-local $::TODO = "RT #111730 - vec uses I32 for offsets";
 
 my $v = "";
 ok(scalar eval { vec($v, 0x80000000, 1) = 1 }, "set a bit at a large offset");
 ok(vec($v, 0x80000000, 1), "check a bit at a large offset");
-{ local $::TODO; # succeeds but shouldn't at this point
+
 ok(scalar eval { vec($v, 0x100000000, 1) = 1 },
    "set a bit at a larger offset");
 ok(vec($v, 0x100000000, 1), "check a bit at a larger offset");
@@ -29,7 +28,6 @@ ok(vec($v, 0x100000000, 1), "check a bit at a larger offset");
 # real out of range values
 ok(!eval { vec($v, -0x80000000, 1) = 1 },
    "shouldn't be able to set at a large negative offset");
-}
 ok(!eval { vec($v, -0x100000000, 1) = 1 },
    "shouldn't be able to set at a larger negative offset");