[clang capture] Don't attach plugin when clang is invoked in preprocessor mode

Summary:
There is no point in attaching plugin to `clang -E` calls since they don't produce any AST.
Same applies to `-M`, `-MM`, etc. (but not `-MD` nor `-MMD`).

Reviewed By: jvillard

Differential Revision: D4681618

fbshipit-source-id: 7a76add

.gitignore

@@ -31,6 +31,7 @@ duplicates.txt
 /infer/tests/build_systems/codetoanalyze/path with spaces/
 /infer/tests/build_systems/clang_compilation_db_escaped/compile_commands.json
 /infer/tests/build_systems/clang_compilation_db_relpath/compile_commands.json
+/infer/tests/build_systems/clang_with_MD_flag/hello.d
 /infer/tests/build_systems/codetoanalyze/xcodebuild/simple_app/app_built
 /infer/tests/build_systems/codetoanalyze/xcodebuild/simple_app/build/
 infer/tests/build_systems/differential_*/**/*.class

Makefile

@@ -21,6 +21,9 @@ BUILD_SYSTEMS_TESTS += \
   clang_multiple_files \
   clang_translation \
   clang_unknown_ext \
+  clang_with_E_flag \
+  clang_with_M_flag \
+  clang_with_MD_flag \
   delete_results_dir \
   differential_resolve_infer_eradicate_conflict \
   differential_skip_anonymous_class_renamings \

infer/src/clang/ClangCommand.re

@@ -53,16 +53,19 @@ let value_of_option {orig_argv} => value_of_argv_option orig_argv;
 
 let has_flag {orig_argv} flag => List.exists f::(String.equal flag) orig_argv;
 
-let can_attach_ast_exporter cmd =>
+let can_attach_ast_exporter cmd => {
-  has_flag cmd "-cc1" && (
+  let is_supported_language cmd =>
     switch (value_of_option cmd "-x") {
     | None =>
       Logging.stderr "malformed -cc1 command has no \"-x\" flag!";
       false
     | Some lang when String.is_prefix prefix::"assembler" lang => false
     | Some _ => true
-    }
+    };
-  );
+  /* -Eonly is -cc1 flag that gets produced by 'clang -M -### ...' */
+  let is_preprocessor_only cmd => has_flag cmd "-E" || has_flag cmd "-Eonly";
+  has_flag cmd "-cc1" && is_supported_language cmd && not (is_preprocessor_only cmd)
+};
 
 let argv_cons a b => [a, ...b];
 

infer/tests/build_systems/clang_with_E_flag/Makefile

@@ -0,0 +1,17 @@
+# Copyright (c) 2017 - present Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+TESTS_DIR = ../..
+
+ANALYZER = infer
+CLANG_OPTIONS = -E -c
+INFER_OPTIONS = --report-custom-error --developer-mode --project-root ../codetoanalyze --no-failures-allowed
+INFERPRINT_OPTIONS = --issues-tests
+
+SOURCES = ../codetoanalyze/hello.c
+
+include $(TESTS_DIR)/clang.make

infer/tests/build_systems/clang_with_MD_flag/Makefile

@@ -0,0 +1,17 @@
+# Copyright (c) 2017 - present Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+TESTS_DIR = ../..
+
+ANALYZER = infer
+CLANG_OPTIONS = -MD -c
+INFER_OPTIONS = --report-custom-error --developer-mode --project-root ../codetoanalyze --no-failures-allowed
+INFERPRINT_OPTIONS = --issues-tests
+
+SOURCES = ../codetoanalyze/hello.c
+
+include $(TESTS_DIR)/clang.make

infer/tests/build_systems/clang_with_MD_flag/issues.exp

@@ -0,0 +1 @@
+hello.c, test, 2, NULL_DEREFERENCE, [start of procedure test()]

infer/tests/build_systems/clang_with_M_flag/Makefile

@@ -0,0 +1,17 @@
+# Copyright (c) 2017 - present Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+TESTS_DIR = ../..
+
+ANALYZER = infer
+CLANG_OPTIONS = -M -c
+INFER_OPTIONS = --report-custom-error --developer-mode --project-root ../codetoanalyze --no-failures-allowed
+INFERPRINT_OPTIONS = --issues-tests
+
+SOURCES = ../codetoanalyze/hello.c
+
+include $(TESTS_DIR)/clang.make