1089370 - content/base/src/nsContentUtils.cpp:4144:11: error: reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Alex Xu]

20:44.07 /home/alex/gecko-dev/content/base/src/nsContentUtils.cpp:4144:11: error: reference cannot be bound to dereferenced null pointer in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]
20:44.08     if (!&tagName) {
20:44.08         ~ ^~~~~~~
20:44.08 1 error generated.
20:44.10 In the directory  /home/alex/gecko-dev/obj-x86_64-unknown-linux-gnu/content/base/src
20:44.10 The following command failed to execute properly:
20:44.10 /usr/bin/ccache clang++ -o nsContentUtils.o -c -I[everything] -fPIC -Qunused-arguments -DMOZILLA_CLIENT -include ../../../mozilla-config.h -MD -MP -MF .deps/nsContentUtils.o.pp -Qunused-arguments -Qunused-arguments -Wall -Wempty-body -Woverloaded-virtual -Wsign-compare -Wwrite-strings -Werror=endif-labels -Werror=int-to-pointer-cast -Werror=missing-braces -Werror=pointer-arith -Werror=return-type -Werror=sequence-point -Werror=unused-label -Werror=trigraphs -Werror=type-limits -Wno-invalid-offsetof -Wno-inline-new-delete -Wno-c++0x-extensions -Wno-extended-offsetof -Wno-unknown-warning-option -Wno-return-type-c-linkage -Wno-error=uninitialized -Wno-error=deprecated-declarations -O2 -pipe -march=native -fstack-protector -march=native -fno-exceptions -fno-strict-aliasing -fno-rtti -fno-exceptions -fno-math-errno -std=gnu++0x -pthread -pipe -DNDEBUG -DTRIMMED -ggdb -Xclang -load -Xclang ../../../build/clang-plugin/libclang-plugin.so -Xclang -add-plugin -Xclang moz-check -O2 -fomit-frame-pointer -Werror /home/alex/gecko-dev/content/base/src/nsContentUtils.cpp
20:44.10 /home/alex/gecko-dev/config/rules.mk:948: recipe for target 'nsContentUtils.o' failed
20:44.10 gmake[5]: *** [nsContentUtils.o] Error 1

Comment 1

[:Ms2ger (he/him; ⌚ UTC+1/+2)]

Attachment: Don't null-check a reference in nsContentUtils::CreateContextualFragment

This triggers an undefined-bool-conversion warning in recent LLVM. The
dereference is safe because nsAutoTArray is infallible.

Comment 2

[:Ms2ger (he/him; ⌚ UTC+1/+2)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/7e8eda44373c

Comment 3

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/7e8eda44373c