997306 - TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare], and many more

Status: RESOLVED FIXED

(Core :: JavaScript: GC, defect)

Description

[Daniel Holbert [:dholbert]]

I noticed these 57 lines go by in my buildspew today, for TestGCPostBarriers.cpp:
{
 3:11.17 In file included from $OBJDIR/xpcom/glue/tests/gtest/Unified_cpp_glue_tests_gtest0.cpp:15:
 3:11.17 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.17 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.17   for (int i = 0; i < ElementCount; ++i) {
 3:11.17                   ~ ^ ~~~~~~~~~~~~
 3:11.17 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.17 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:79:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.17   for (int i = 0; i < ElementCount; ++i) {
 3:11.17                   ~ ^ ~~~~~~~~~~~~
 3:11.18 TestComponent.o
 3:11.18 nsEnumeratorUtils.o
 3:11.27 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.27 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.27   for (int i = 0; i < ElementCount; ++i) {
 3:11.27                   ~ ^ ~~~~~~~~~~~~
 3:11.27 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:113:5: note: in instantiation of function template specialization 'RunTest<nsTArray<JS::Heap<JSObject *> > >' requested here
 3:11.27     RunTest(rt, cx, array);
 3:11.27     ^
 3:11.27 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.27 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:79:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.27   for (int i = 0; i < ElementCount; ++i) {
 3:11.27                   ~ ^ ~~~~~~~~~~~~
 3:11.27 TestComponent.o
 3:11.28 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.28 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.28   for (int i = 0; i < ElementCount; ++i) {
 3:11.28                   ~ ^ ~~~~~~~~~~~~
 3:11.28 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:119:5: note: in instantiation of function template specialization 'RunTest<FallibleTArray<JS::Heap<JSObject *> > >' requested here
 3:11.28     RunTest(rt, cx, array);
 3:11.28     ^
 3:11.28 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.28 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:79:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.28   for (int i = 0; i < ElementCount; ++i) {
 3:11.28                   ~ ^ ~~~~~~~~~~~~
 3:11.28 nsTestSample.o
 3:11.28 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.28 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.28   for (int i = 0; i < ElementCount; ++i) {
 3:11.28                   ~ ^ ~~~~~~~~~~~~
 3:11.28 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:125:5: note: in instantiation of function template specialization 'RunTest<nsAutoTArray<JS::Heap<JSObject *>, 10> >' requested here
 3:11.28     RunTest(rt, cx, &array);
 3:11.28     ^
 3:11.29 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.29 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:79:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.29   for (int i = 0; i < ElementCount; ++i) {
 3:11.29                   ~ ^ ~~~~~~~~~~~~
 3:11.29 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.29 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:58:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.29   for (int i = 0; i < ElementCount; ++i) {
 3:11.29                   ~ ^ ~~~~~~~~~~~~
 3:11.29 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:130:5: note: in instantiation of function template specialization 'RunTest<AutoFallibleTArray<JS::Heap<JSObject *>, 10> >' requested here
 3:11.29     RunTest(rt, cx, &array);
 3:11.29     ^
 3:11.29 Warning: -Wsign-compare in $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long')
 3:11.29 $SRCDIR/xpcom/glue/tests/gtest/TestGCPostBarriers.cpp:79:21: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
 3:11.29   for (int i = 0; i < ElementCount; ++i) {
 3:11.29                   ~ ^ ~~~~~~~~~~~~
}

Looks like Bug 993410 introduced 'ElementCount' and made these comparisons into signed/unsigned comparisons; hence, setting as blocking that bug.

(I'm building with clang 3.4 on linux, if it matters -- though I think all compilers should warn about this.)

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: fix v1

This patch makes the test compile with no warnings for me.

Comment 2

[Daniel Holbert [:dholbert]]

Attachment: fix v2

[minor tweak: changed my static_cast to use int32_t instead of int, to match the return-type of value.toInt32().]

Comment 3

[Jon Coppeard (:jonco)]

Comment on attachment 8407692 [details] [diff] [review]
fix v2

Review of attachment 8407692 [details] [diff] [review]:
-----------------------------------------------------------------

Thanks for fixing this!

Comment 4

[Daniel Holbert [:dholbert]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/1ee7dd06327f

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/1ee7dd06327f