[PATCH] D52524: Add -Wpoison-system-directories warning

[Manoj Gupta via Phabricator via cfe-commits]

manojgupta added a comment.

An earlier version did check for library directories [1]. I am not exactly sure 
why was it removed, maybe it didn't work. So if anyone is willing to test that, 
please apply the diff and try.

[1] Diff https://reviews.llvm.org/D52524?id=215958


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added a comment.

In D52524#2721073 , @sbc100 wrote:

> Would it make sense to have this apply to system library paths too?   i.e. 
> `-L/usr/local/lib`.
>
> We have a bespoke mechanism in emscripten right now that is a bit more 
> flexible but I'd love to simple replace it with `-Wpoison-system-directories`.
>
> The name "system directories" seems to imply that it should apply to both 
> include and library directories.  It also looks like the gcc version applies 
> to both `Warn for -I and -L options using system directories if cross 
> compiling` (from 
> https://github.com/Metrological/buildroot/blob/master/package/gcc/4.8.4/910-gcc-poison-system-directories.patch).

FWIW, I think it would make sense to support library paths as well.


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Sam Clegg via Phabricator via cfe-commits]

sbc100 added a comment.

Would it make sense to have this apply to system library paths too?   i.e. 
`-L/usr/local/lib`.

We have a bespoke mechanism in emscripten right now that is a bit more flexible 
but I'd love to simple replace it with `-Wpoison-system-directories`.

The name "system directories" seems to imply that it should apply to both 
include and library directories.  It also looks like the gcc version applies to 
both `Warn for -I and -L options using system directories if cross compiling` 
(from 
https://github.com/Metrological/buildroot/blob/master/package/gcc/4.8.4/910-gcc-poison-system-directories.patch).


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Manoj Gupta via Phabricator via cfe-commits]

manojgupta closed this revision.
manojgupta added a comment.

Submitted as https://reviews.llvm.org/rL371785.
Thanks for the patch!


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik marked 2 inline comments as done.
denik added inline comments.



Comment at: clang/lib/Frontend/InitHeaderSearch.cpp:141-143
+  if (HasSysroot) {
+if (MappedPathStr.startswith("/usr/include") ||
+MappedPathStr.startswith("/usr/local/include")) {

aaron.ballman wrote:
> These should be combined into a single if statement:
> ```
> if (HasSysroot && (MappedPathStr.startswith(...) || 
> MappedPathStr.startswith(...))) {
> ```
Done.


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik updated this revision to Diff 219924.
denik added a comment.

Combined two if into one.


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Files:
  clang/include/clang/Basic/DiagnosticCommonKinds.td
  clang/lib/Frontend/InitHeaderSearch.cpp
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep
  clang/test/Frontend/warning-poison-system-directories.c


Index: clang/test/Frontend/warning-poison-system-directories.c
===
--- /dev/null
+++ clang/test/Frontend/warning-poison-system-directories.c
@@ -0,0 +1,27 @@
+// 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]
Index: clang/lib/Frontend/InitHeaderSearch.cpp
===
--- clang/lib/Frontend/InitHeaderSearch.cpp
+++ clang/lib/Frontend/InitHeaderSearch.cpp
@@ -137,6 +137,13 @@
   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) {
Index: clang/include/clang/Basic/DiagnosticCommonKinds.td
===
--- clang/include/clang/Basic/DiagnosticCommonKinds.td
+++ clang/include/clang/Basic/DiagnosticCommonKinds.td
@@ -315,4 +315,9 @@
 "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;
 }


Index: clang/test/Frontend/warning-poison-system-directories.c
===
--- /dev/null
+++ clang/test/Frontend/warning-poison-system-directories.c
@@ -0,0 +1,27 @@
+// 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 

[PATCH] D52524: Add -Wpoison-system-directories warning

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman accepted this revision.
aaron.ballman added a comment.
This revision is now accepted and ready to land.

Aside from a minor nit, this LGTM. However, I'm not the most familiar with how 
cross-compiling works in the first place, so I may be the wrong one to approve 
this.




Comment at: clang/lib/Frontend/InitHeaderSearch.cpp:141-143
+  if (HasSysroot) {
+if (MappedPathStr.startswith("/usr/include") ||
+MappedPathStr.startswith("/usr/local/include")) {

These should be combined into a single if statement:
```
if (HasSysroot && (MappedPathStr.startswith(...) || 
MappedPathStr.startswith(...))) {
```


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik added a comment.

Ping @aaron.ballman , please verify the change.


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik added a comment.

Hi Aaron,

Thank you for your review. I updated the diff with suggested changes.




Comment at: clang/include/clang/Basic/DiagnosticGroups.td:1072
+// cross-compiling.
+def PoisonSystemDirectories : DiagGroup<"poison-system-directories">;
+

aaron.ballman wrote:
> Do you envision more warnings being added to this group? If not, I would 
> recommend dropping this change and instead using 
> `InGroup>` in the diagnostic.
Added the change. Thanks.



Comment at: clang/lib/Frontend/InitHeaderSearch.cpp:145
+  Headers.getDiags().Report(diag::warn_poison_system_directories)
+  << MappedPathStr.str();
+}

aaron.ballman wrote:
> I don't think you need the `.str()` here.
Thank you for pointing out. Fixed.


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik updated this revision to Diff 217746.
denik marked 4 inline comments as done.

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Files:
  clang/include/clang/Basic/DiagnosticCommonKinds.td
  clang/lib/Frontend/InitHeaderSearch.cpp
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep
  clang/test/Frontend/warning-poison-system-directories.c


Index: clang/test/Frontend/warning-poison-system-directories.c
===
--- /dev/null
+++ clang/test/Frontend/warning-poison-system-directories.c
@@ -0,0 +1,27 @@
+// 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]
Index: clang/lib/Frontend/InitHeaderSearch.cpp
===
--- clang/lib/Frontend/InitHeaderSearch.cpp
+++ clang/lib/Frontend/InitHeaderSearch.cpp
@@ -137,6 +137,15 @@
   SmallString<256> MappedPathStorage;
   StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
 
+  // If use system headers while cross-compiling, emit the warning.
+  if (HasSysroot) {
+if (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) {
Index: clang/include/clang/Basic/DiagnosticCommonKinds.td
===
--- clang/include/clang/Basic/DiagnosticCommonKinds.td
+++ clang/include/clang/Basic/DiagnosticCommonKinds.td
@@ -309,4 +309,9 @@
 "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;
 }


Index: clang/test/Frontend/warning-poison-system-directories.c
===
--- /dev/null
+++ clang/test/Frontend/warning-poison-system-directories.c
@@ -0,0 +1,27 @@
+// 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 

[PATCH] D52524: Add -Wpoison-system-directories warning

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.



Comment at: clang/include/clang/Basic/DiagnosticGroups.td:1072
+// cross-compiling.
+def PoisonSystemDirectories : DiagGroup<"poison-system-directories">;
+

Do you envision more warnings being added to this group? If not, I would 
recommend dropping this change and instead using 
`InGroup>` in the diagnostic.



Comment at: clang/lib/Frontend/InitHeaderSearch.cpp:145
+  Headers.getDiags().Report(diag::warn_poison_system_directories)
+  << MappedPathStr.str();
+}

I don't think you need the `.str()` here.


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[PATCH] D52524: Add -Wpoison-system-directories warning

[Denis Nikitin via Phabricator via cfe-commits]

denik updated this revision to Diff 216021.
denik added a comment.

Removed check for libraries.


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Files:
  clang/include/clang/Basic/DiagnosticCommonKinds.td
  clang/include/clang/Basic/DiagnosticGroups.td
  clang/lib/Frontend/InitHeaderSearch.cpp
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/lib/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/include/c++/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/lib/gcc/.keep
  
clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/include/.keep
  clang/test/Frontend/Inputs/sysroot_x86_64_cross_linux_tree/usr/local/lib/.keep
  clang/test/Frontend/warning-poison-system-directories.c


Index: clang/test/Frontend/warning-poison-system-directories.c
===
--- /dev/null
+++ clang/test/Frontend/warning-poison-system-directories.c
@@ -0,0 +1,27 @@
+// 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]
Index: clang/lib/Frontend/InitHeaderSearch.cpp
===
--- clang/lib/Frontend/InitHeaderSearch.cpp
+++ clang/lib/Frontend/InitHeaderSearch.cpp
@@ -137,6 +137,15 @@
   SmallString<256> MappedPathStorage;
   StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
 
+  // If use system headers while cross-compiling, emit the warning.
+  if (HasSysroot) {
+if (MappedPathStr.startswith("/usr/include") ||
+MappedPathStr.startswith("/usr/local/include")) {
+  Headers.getDiags().Report(diag::warn_poison_system_directories)
+  << MappedPathStr.str();
+}
+  }
+
   // Compute the DirectoryLookup type.
   SrcMgr::CharacteristicKind Type;
   if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) {
Index: clang/include/clang/Basic/DiagnosticGroups.td
===
--- clang/include/clang/Basic/DiagnosticGroups.td
+++ clang/include/clang/Basic/DiagnosticGroups.td
@@ -1067,6 +1067,10 @@
 // multiversioning.
 def FunctionMultiVersioning : DiagGroup<"function-multiversion">;
 
+// A warning group for warnings about including system headers when
+// cross-compiling.
+def PoisonSystemDirectories : DiagGroup<"poison-system-directories">;
+
 def NoDeref : DiagGroup<"noderef">;
 
 // A group for cross translation unit static analysis related warnings.
Index: clang/include/clang/Basic/DiagnosticCommonKinds.td
===
--- clang/include/clang/Basic/DiagnosticCommonKinds.td
+++ clang/include/clang/Basic/DiagnosticCommonKinds.td
@@ -304,4 +304,9 @@
 "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