Author: enrico
Date: Wed May 25 18:19:01 2016
New Revision: 270793
URL: http://llvm.org/viewvc/llvm-project?rev=270793&view=rev
Log:
It has been brought to my attention that, given two variables
T x;
U y;
doing
x = *((T*)y)
is undefined behavior, even if sizeof(T) == sizeof(U), due to pointer aliasing
rules
Fix up a couple of places in LLDB that were doing this, and transform them into
a defined and safe memcpy() operation
Also, add a test case to ensure we didn't regress by doing this w.r.t. tagged
pointer NSDate instances
Modified:
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/TestDataFormatterObjC.py
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/main.m
lldb/trunk/source/Plugins/Language/ObjC/Cocoa.cpp
Modified:
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/TestDataFormatterObjC.py
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/TestDataFormatterObjC.py?rev=270793&r1=270792&r2=270793&view=diff
==============================================================================
---
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/TestDataFormatterObjC.py
(original)
+++
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/TestDataFormatterObjC.py
Wed May 25 18:19:01 2016
@@ -271,16 +271,18 @@ class ObjCDataFormatterTestCase(TestBase
# this test might fail if we hit the breakpoint late on December 31st
of some given year
# and midnight comes between hitting the breakpoint and running this
line of code
# hopefully the output will be revealing enough in that case :-)
- now_year = str(datetime.datetime.now().year)
+ now_year = '%s-' % str(datetime.datetime.now().year)
- self.expect('frame variable date3 date4',
- substrs = [now_year,'1970'])
+ self.expect('frame variable date3', substrs = [now_year])
+ self.expect('frame variable date4', substrs = ['1970'])
+ self.expect('frame variable date5', substrs = [now_year])
self.expect('frame variable date1_abs date2_abs',
substrs = ['1985-04','2011-01'])
- self.expect('frame variable date3_abs date4_abs',
- substrs = [now_year,'1970'])
+ self.expect('frame variable date3_abs', substrs = [now_year])
+ self.expect('frame variable date4_abs', substrs = ['1970'])
+ self.expect('frame variable date5_abs', substrs = [now_year])
self.expect('frame variable cupertino home europe',
substrs = ['@"America/Los_Angeles"',
@@ -358,7 +360,6 @@ class ObjCDataFormatterTestCase(TestBase
self.runCmd('type format clear', check=False)
self.runCmd('type summary clear', check=False)
self.runCmd('type synth clear', check=False)
- self.runCmd('log timers disable', check=False)
# Execute the cleanup function during test case tear down.
Modified:
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/main.m
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/main.m?rev=270793&r1=270792&r2=270793&view=diff
==============================================================================
---
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/main.m
(original)
+++
lldb/trunk/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/main.m
Wed May 25 18:19:01 2016
@@ -489,11 +489,13 @@ int main (int argc, const char * argv[])
NSDate *date2 = [NSDate dateWithNaturalLanguageString:@"12am
January 1, 2011"];
NSDate *date3 = [NSDate date];
NSDate *date4 = [NSDate dateWithTimeIntervalSince1970:24*60*60];
+ NSDate *date5 = [NSDate dateWithTimeIntervalSinceReferenceDate:
floor([[NSDate date] timeIntervalSinceReferenceDate])];
CFAbsoluteTime date1_abs = CFDateGetAbsoluteTime(date1);
CFAbsoluteTime date2_abs = CFDateGetAbsoluteTime(date2);
CFAbsoluteTime date3_abs = CFDateGetAbsoluteTime(date3);
CFAbsoluteTime date4_abs = CFDateGetAbsoluteTime(date4);
+ CFAbsoluteTime date5_abs = CFDateGetAbsoluteTime(date5);
NSIndexSet *iset1 = [[NSIndexSet alloc]
initWithIndexesInRange:NSMakeRange(1, 4)];
NSIndexSet *iset2 = [[NSIndexSet alloc]
initWithIndexesInRange:NSMakeRange(1, 512)];
Modified: lldb/trunk/source/Plugins/Language/ObjC/Cocoa.cpp
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Language/ObjC/Cocoa.cpp?rev=270793&r1=270792&r2=270793&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/Language/ObjC/Cocoa.cpp (original)
+++ lldb/trunk/source/Plugins/Language/ObjC/Cocoa.cpp Wed May 25 18:19:01 2016
@@ -536,7 +536,8 @@ lldb_private::formatters::NSNumberSummar
uint32_t flt_as_int =
process_sp->ReadUnsignedIntegerFromMemory(data_location, 4, 0, error);
if (error.Fail())
return false;
- float flt_value = *((float*)&flt_as_int);
+ float flt_value = 0.0f;
+ memcpy(&flt_value, &flt_as_int, sizeof(flt_as_int));
NSNumber_FormatFloat(valobj, stream, flt_value,
options.GetLanguage());
break;
}
@@ -545,7 +546,8 @@ lldb_private::formatters::NSNumberSummar
uint64_t dbl_as_lng =
process_sp->ReadUnsignedIntegerFromMemory(data_location, 8, 0, error);
if (error.Fail())
return false;
- double dbl_value = *((double*)&dbl_as_lng);
+ double dbl_value = 0.0;
+ memcpy(&dbl_value, &dbl_as_lng, sizeof(dbl_as_lng));
NSNumber_FormatDouble(valobj, stream, dbl_value,
options.GetLanguage());
break;
}
@@ -666,7 +668,7 @@ lldb_private::formatters::NSDateSummaryP
if (descriptor->GetTaggedPointerInfo(&info_bits,&value_bits))
{
date_value_bits = ((value_bits << 8) | (info_bits << 4));
- date_value = *((double*)&date_value_bits);
+ memcpy(&date_value, &date_value_bits, sizeof(date_value_bits));
}
else
{
@@ -674,7 +676,7 @@ lldb_private::formatters::NSDateSummaryP
uint32_t delta = (triple.isWatchOS() && triple.isWatchABI()) ? 8 :
ptr_size;
Error error;
date_value_bits =
process_sp->ReadUnsignedIntegerFromMemory(valobj_addr+delta, 8, 0, error);
- date_value = *((double*)&date_value_bits);
+ memcpy(&date_value, &date_value_bits, sizeof(date_value_bits));
if (error.Fail())
return false;
}
@@ -683,7 +685,7 @@ lldb_private::formatters::NSDateSummaryP
{
Error error;
date_value_bits =
process_sp->ReadUnsignedIntegerFromMemory(valobj_addr+2*ptr_size, 8, 0, error);
- date_value = *((double*)&date_value_bits);
+ memcpy(&date_value, &date_value_bits, sizeof(date_value_bits));
if (error.Fail())
return false;
}
@@ -940,7 +942,7 @@ lldb_private::formatters::GetOSXEpoch ()
tm_epoch.tm_min = 0;
tm_epoch.tm_mon = 0;
tm_epoch.tm_mday = 1;
- tm_epoch.tm_year = 2001-1900; // for some reason, we need to subtract
1900 from this field. not sure why.
+ tm_epoch.tm_year = 2001-1900;
tm_epoch.tm_isdst = -1;
tm_epoch.tm_gmtoff = 0;
tm_epoch.tm_zone = nullptr;
_______________________________________________
lldb-commits mailing list
lldb-commits@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
