From 41d9d5092a17e60615077da6ef22b4f5cfae2c2e Mon Sep 17 00:00:00 2001 From: Manoj Gupta Date: Fri, 13 Sep 2019 18:00:51 +0000 Subject: [PATCH] Reland r371785: Add -Wpoison-system-directories warning When using clang as a cross-compiler, we should not use system headers to do the compilation. This CL adds support of a new warning flag -Wpoison-system-directories which emits warnings if --sysroot is set and headers from common host system location are used. By default the warning is disabled. The intention of the warning is to catch bad includes which are usually generated by third party build system not targeting cross-compilation. Such cases happen in Chrome OS when someone imports a new package or upgrade one to a newer version from upstream. This is reland of r371785 with a fix to test file. Patch by: denik (Denis Nikitin) llvm-svn: 371878 --- clang/include/clang/Basic/DiagnosticCommonKinds.td | 5 ++++ clang/lib/Frontend/InitHeaderSearch.cpp | 7 ++++++ .../sysroot_x86_64_cross_linux_tree/lib/.keep | 0 .../usr/include/c++/.keep | 0 .../usr/lib/gcc/.keep | 0 .../usr/local/include/.keep | 0 .../usr/local/lib/.keep | 0 .../Frontend/warning-poison-system-directories.c | 29 ++++++++++++++++++++++ 8 files changed, 41 insertions(+) create mode 100644 clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep create mode 100644 clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep create mode 100644 clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep create mode 100644 clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep create mode 100644 clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep create mode 100644 clang/test/Frontend/warning-poison-system-directories.c diff --git a/clang/include/clang/Basic/DiagnosticCommonKinds.td b/clang/include/clang/Basic/DiagnosticCommonKinds.td index 8196a46..1cd62d1 100644 --- a/clang/include/clang/Basic/DiagnosticCommonKinds.td +++ b/clang/include/clang/Basic/DiagnosticCommonKinds.td @@ -315,4 +315,9 @@ def err_unknown_analyzer_checker_or_package : Error< "no analyzer checkers or packages are associated with '%0'">; def note_suggest_disabling_all_checkers : Note< "use -analyzer-disable-all-checks to disable all static analyzer checkers">; + +// Poison system directories. +def warn_poison_system_directories : Warning < + "include location '%0' is unsafe for cross-compilation">, + InGroup>, DefaultIgnore; } diff --git a/clang/lib/Frontend/InitHeaderSearch.cpp b/clang/lib/Frontend/InitHeaderSearch.cpp index ad0d232..5d877ee 100644 --- a/clang/lib/Frontend/InitHeaderSearch.cpp +++ b/clang/lib/Frontend/InitHeaderSearch.cpp @@ -137,6 +137,13 @@ bool InitHeaderSearch::AddUnmappedPath(const Twine &Path, IncludeDirGroup Group, SmallString<256> MappedPathStorage; StringRef MappedPathStr = Path.toStringRef(MappedPathStorage); + // If use system headers while cross-compiling, emit the warning. + if (HasSysroot && (MappedPathStr.startswith("/usr/include") || + MappedPathStr.startswith("/usr/local/include"))) { + Headers.getDiags().Report(diag::warn_poison_system_directories) + << MappedPathStr; + } + // Compute the DirectoryLookup type. SrcMgr::CharacteristicKind Type; if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) { diff --git a/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep b/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep new file mode 100644 index 0000000..e69de29 diff --git a/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep b/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep new file mode 100644 index 0000000..e69de29 diff --git a/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep b/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep new file mode 100644 index 0000000..e69de29 diff --git a/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep b/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep new file mode 100644 index 0000000..e69de29 diff --git a/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep b/clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep new file mode 100644 index 0000000..e69de29 diff --git a/clang/test/Frontend/warning-poison-system-directories.c b/clang/test/Frontend/warning-poison-system-directories.c new file mode 100644 index 0000000..ba4c0e1 --- /dev/null +++ b/clang/test/Frontend/warning-poison-system-directories.c @@ -0,0 +1,29 @@ +// REQUIRES: x86-registered-target + +// System directory and sysroot option causes warning. +// RUN: %clang -Wpoison-system-directories -target x86_64 -I/usr/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.1.stderr +// RUN: FileCheck -check-prefix=WARN < %t.1.stderr %s +// RUN: %clang -Wpoison-system-directories -target x86_64 -cxx-isystem/usr/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.1.stderr +// RUN: FileCheck -check-prefix=WARN < %t.1.stderr %s +// RUN: %clang -Wpoison-system-directories -target x86_64 -iquote/usr/local/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.1.stderr +// RUN: FileCheck -check-prefix=WARN < %t.1.stderr %s +// RUN: %clang -Wpoison-system-directories -target x86_64 -isystem/usr/local/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.1.stderr +// RUN: FileCheck -check-prefix=WARN < %t.1.stderr %s + +// Missing target but included sysroot still causes the warning. +// RUN: %clang -Wpoison-system-directories -I/usr/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.2.stderr +// RUN: FileCheck -check-prefix=WARN < %t.2.stderr %s + +// With -Werror the warning causes the failure. +// RUN: not %clang -Werror=poison-system-directories -target x86_64 -I/usr/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s 2> %t.3.stderr +// RUN: FileCheck -check-prefix=ERROR < %t.3.stderr %s + +// Cros target without sysroot causes no warning. +// RUN: %clang -Wpoison-system-directories -Werror -target x86_64 -I/usr/include -c -o - %s + +// By default the warning is off. +// RUN: %clang -Werror -target x86_64 -I/usr/include --sysroot %S/Inputs/sysroot_x86_64_cross_linux_tree -c -o - %s + +// WARN: warning: include location {{[^ ]+}} is unsafe for cross-compilation [-Wpoison-system-directories] + +// ERROR: error: include location {{[^ ]+}} is unsafe for cross-compilation [-Werror,-Wpoison-system-directories] -- 2.7.4