Extended Description

Reduced by bugpoint. The issue is that this testcase:

target datalayout = "e-p:32:32"
target endian = little
target pointersize = 32
target triple = "i686-apple-darwin8"
%struct.Connector = type { i16, i16, i8, i8, %struct.Connector*, i8* }

implementation ; Functions:

define bool %prune_match_entry_2E_ce(%struct.Connector* %a, i16 %b.0.0.val) {
newFuncRoot:
br label %entry.ce

cond_next.exitStub: ; preds = %entry.ce
ret bool true

entry.return_crit_edge.exitStub: ; preds = %entry.ce
ret bool false

entry.ce: ; preds = %newFuncRoot
%tmp = getelementptr %struct.Connector* %a, i32 0, i32 0 ; <i16*> [#uses=1]
%tmp = load i16* %tmp ; [#uses=1]
%tmp = icmp eq i16 %tmp, %b.0.0.val ; [#uses=1]
br bool %tmp, label %cond_next.exitStub, label %entry.return_crit_edge.exitStub
}

is compiled to:

struct l_struct_2E_Connector {
signed short field0;
signed short field1;
signed char field2;
signed char field3;
struct l_struct_2E_Connector *field4;
signed char *field5;
};
...
bool prune_match_entry_2E_ce(struct l_struct_2E_Connector *ltmp_0_1, unsigned short ltmp_1_2) {
signed short ltmp_2_2;

ltmp_2_2 = *(&ltmp_0_1->field0);
return ((((ltmp_2_2 == ltmp_1_2)) ? (1) : (0)));
}

Note that the == is comparing a signed short and an unsigned short. These both get extended
(differently) to int before the comparison is done.

-Chris