How to make CLion to recognize .c files as c++ (and not as plain c)

Question

By default CLion C and C++ files has united file type in Settings->Editor->File Types But in inspect code .c file recognize as plain C (for example type bool requires the inclusion < stdbool.h >) but actually it must be compiled as C++

Help->About: CLion CL-140.2310.6 Build #CL-140.2310, built on February 12, 2015 ...

Answer 1

for CMakeLists.txt project (without clangd completion)

Put

SET_SOURCE_FILES_PROPERTIES(${SOURCE_FILES} PROPERTIES LANGUAGE CXX)

in your CMakeLists.txt.

• https://intellij-support.jetbrains.com/hc/en-us/community/posts/205822539/comments/205713325
• https://cmake.org/cmake/help/latest/command/set_source_files_properties.html
• https://cmake.org/cmake/help/latest/prop_sf/LANGUAGE.html

As commented by user7610 below this seems not to work when clangd completion is enabled (though I haven't confirmed it yet).

for compilation database project

insert ""-xc++"," to [].arguments[1] in compile_commands.json.

--- compile_commands_original.json  2022-03-10 12:08:05.025572787 +0900
+++ compile_commands.json   2022-03-10 12:09:16.250045217 +0900
@@ -12663,6 +12663,7 @@
     {
         "arguments": [
             "g++",
+            "-xc++",
             "-c",
             "-std=c++11",
             "-fno-PIE",

(This happens when I build gcc with bear.)