fails to build on debian sid

[ju1ius]

Hi,

Building ada-url on debian sid fails.
Running the following commands:

git clone --depth=1 https://github.com/ada-url/rust.git ada-url
cd ada-url
cargo build

Produces the following output:

   Compiling ada-url v2.2.1 (/ada-url)
The following warnings were emitted during compilation:

warning: ada-url@2.2.1: In file included from ./deps/ada.cpp:3:
warning: ada-url@2.2.1: ./deps/ada.h:20:10: fatal error: 'string' file not found
warning: ada-url@2.2.1: #include <string>
warning: ada-url@2.2.1:          ^~~~~~~~
warning: ada-url@2.2.1: 1 error generated.

error: failed to run custom build command for `ada-url v2.2.1 (/ada-url)`

Caused by:
  process didn't exit successfully: `/ada-url/target/debug/build/ada-url-ba3156cf87bc7d44/build-script-build` (exit status: 1)
  --- stdout
  OPT_LEVEL = Some("0")
  TARGET = Some("x86_64-unknown-linux-gnu")
  HOST = Some("x86_64-unknown-linux-gnu")
  cargo:rerun-if-env-changed=CXX_x86_64-unknown-linux-gnu
  CXX_x86_64-unknown-linux-gnu = None
  cargo:rerun-if-env-changed=CXX_x86_64_unknown_linux_gnu
  CXX_x86_64_unknown_linux_gnu = None
  cargo:rerun-if-env-changed=HOST_CXX
  HOST_CXX = None
  cargo:rerun-if-env-changed=CXX
  CXX = Some("clang++")
  cargo:rerun-if-env-changed=CRATE_CC_NO_DEFAULTS
  CRATE_CC_NO_DEFAULTS = None
  DEBUG = Some("true")
  cargo:rerun-if-env-changed=CXXFLAGS_x86_64-unknown-linux-gnu
  CXXFLAGS_x86_64-unknown-linux-gnu = None
  cargo:rerun-if-env-changed=CXXFLAGS_x86_64_unknown_linux_gnu
  CXXFLAGS_x86_64_unknown_linux_gnu = None
  cargo:rerun-if-env-changed=HOST_CXXFLAGS
  HOST_CXXFLAGS = None
  cargo:rerun-if-env-changed=CXXFLAGS
  CXXFLAGS = None
  running: "clang++" "-O0" "-ffunction-sections" "-fdata-sections" "-fPIC" "-gdwarf-4" "-fno-omit-frame-pointer" "--target=x86_64-unknown-linux-gnu" "-std=c++17" "-I" "./deps/ada.h" "-I" "./deps/ada_c.h" "-Wall" "-Wextra" "-o" "/ada-url/target/debug/build/ada-url-b4939785ec9bcc43/out/./deps/ada.o" "-c" "./deps/ada.cpp"
  cargo:warning=In file included from ./deps/ada.cpp:3:

  cargo:warning=./deps/ada.h:20:10: fatal error: 'string' file not found

  cargo:warning=#include <string>

  cargo:warning=         ^~~~~~~~

  cargo:warning=1 error generated.

  exit status: 1

  --- stderr


  error occurred: Command "clang++" "-O0" "-ffunction-sections" "-fdata-sections" "-fPIC" "-gdwarf-4" "-fno-omit-frame-pointer" "--target=x86_64-unknown-linux-gnu" "-std=c++17" "-I" "./deps/ada.h" "-I" "./deps/ada_c.h" "-Wall" "-Wextra" "-o" "/ada-url/target/debug/build/ada-url-b4939785ec9bcc43/out/./deps/ada.o" "-c" "./deps/ada.cpp"with args "clang++" did not execute successfully (status code exit status: 1).

It seems that clang cannot find the c++ stdlib... 🤔
Moreover, the build script unconditionally sets the compiler to clang++, which makes trying another compiler (or another clang version) impossible.

If I comment out the aforementioned line and build with CXX=g++ cargo build, the library builds correctly and tests pass:

$ CXX=g++ cargo build
   Compiling ada-url v2.2.1 (/ada-url)
warning: ada-url@2.2.1: cc1plus: warning: ./deps/ada.h: not a directory
warning: ada-url@2.2.1: cc1plus: warning: ./deps/ada_c.h: not a directory
    Finished dev [unoptimized + debuginfo] target(s) in 3.57s

Also note the warnings caused by the build script's passing files to cc::Build::include() instead of directories.

IMO, the build script should let the cc crate detect the correct compiler on UNIX platforms.

[anonrig]

Can you install libc++ to your system, and re-test it? It seems similar to #43

[anonrig]

IMO, the build script should let the cc crate detect the correct compiler on UNIX platforms.

Would you like to open a PR?

[ju1ius]

Can you install libc++ to your system, and re-test it? It seems similar to #43

After installing the libc++-dev package:

$ clang++ -O0 -std=c++17 -o ./ada.o -c ./deps/ada.cpp
In file included from ./deps/ada.cpp:3:
./deps/ada.h:20:10: fatal error: 'string' file not found
#include <string>
         ^~~~~~~~
1 error generated.

And

$ clang++ -O0 -std=c++17 -stdlib=libc++ -o ./ada.o -c ./deps/ada.cpp

So it seems that somehow clang cannot use the gcc version of the c++ stdlib on debian...
That's weird, cause I'm pretty sure it used to work. Maybe it broke in a recent update...

Anyway, since gcc can compile the library just fine, I still think the compiler shouldn't be forced on end users.

Would you like to open a PR?

OK, I'll do.