vcpkg fatal error: 'muParser.h' file not found even though the file exists

Question

I have OS X Mojave.

I'm trying out vcpkg and even though I installed muParser and it exists at ‎⁨Macintosh HD⁩ ▸ ⁨Users⁩ ▸ ⁨dchambers⁩ ▸ ⁨vcpkg⁩ ▸ ⁨installed⁩ ▸ ⁨x64-osx⁩ ▸ ⁨include⁩ AND I get no red underlining on #include "muParser.h" but DO on a deliberate typo such as #include "muParserX.h" I get the error:

test.cpp:2:10: fatal error: 'muParser.h' file not found include "muParser.h"

...when I try to build.

As a test, I included a header #include "gmp.h" from the 'normal' path: /usr/local/Cellar/gmp/6.1.2_2/include/gmp.h (actually an alias from usr/local/include) and all is fine for that.

Here's my Visual Studio Code setup and the file:

test.cpp:

#include <iostream>
#include "muParser.h"
#include "gmp.h"

int main(int argc, const char * argv[]) {
// insert code here...
std::cout << "Hello, World!\n";

return 0;
}

c_cpp_properties.json:

{
"configurations": [
    {
        "name": "Mac",
        "includePath": [
            "${workspaceFolder}/**",
            "${vcpkgRoot}/x64-osx/include"
        ],
        "defines": [],
        "macFrameworkPath": [
            "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/System/Library/Frameworks"
        ],
        "compilerPath": "/usr/bin/clang",
        "cStandard": "c11",
        "cppStandard": "c++17",
        "intelliSenseMode": "clang-x64"
    }
],
"version": 4
}

tasks.json:

{
// See https://go.microsoft.com/fwlink/?LinkId=733558
// for the documentation about the tasks.json format
"version": "2.0.0",
"tasks": [
    {
        "label": "echo",
        "type": "shell",
        "command": "g++",
        "args": [
            "test.cpp"
        ],
        "group": {
            "kind": "build",
            "isDefault": true
        }
    }
]
}

Any ideas?

UPDATE:

This is a problem with Visual Studio Code, described here.

From the command line, the following works fine, telling the command where the libs are:

g++ -I ~/vcpkg/installed/x64-osx/include/ test.cpp. Thanks to roschuma for his answer.

Answer 1

This is a discrepancy between the intellisense engine running in VSCode (which powers the squiggles) and your actual compilation command line (which powers the compile errors) :)

Specifically, you'll need to add "-I${vcpkgRoot}/x64-osx/include" to the list of g++ arguments in the second file.