[bug] When cross building AutotoolsToolchain does not pass --build option if there is any configure argument with "build" in its name

[ovostrikov]

Environment Details

• Operating System+version: WSL Ubuntu 20.04
• Compiler+version: clang 15
• Conan version: 1.54
• Python version: 3.8

Steps to reproduce

conan new at/1.0.0 -t -m autotools_lib

Edit the conanfile generate method to add

    def generate(self):
        at_toolchain = AutotoolsToolchain(self)
        at_toolchain.configure_args.append(f"--with-cross-build=some_path")
        at_toolchain.generate()

Create cross-build-profile file

include(default)
[settings]
os=Emscripten
os_build=Linux
arch=wasm
arch_build=x86_64

Run

conan create . --profile=cross-build-profile --profile:build=default -tf=None  > log.txt
grep '\--build' log.txt

Expected result

The '--build=x86_64-linux-gnu' option should be present:

> '--disable-shared' '--enable-static' '--prefix=/' '--bindir=${prefix}/bin' '--sbindir=${prefix}/bin' '--libdir=${prefix}/lib' '--includedir=${prefix}/include' '--oldincludedir=${prefix}/include' '--with-cross-build=some_path' '--host=wasm32-local-emscripten' '--build=x86_64-linux-gnu'

Actual result

The '--build=x86_64-linux-gnu' option is missing

'--disable-shared' '--enable-static' '--prefix=/' '--bindir=${prefix}/bin' '--sbindir=${prefix}/bin' '--libdir=${prefix}/lib' '--includedir=${prefix}/include' '--oldincludedir=${prefix}/include' '--with-cross-build=some_path' '--host=wasm32-local-emscripten'

Possible cause

AutotoolsToolchain checks that build option has not been set yet. However, since it's a simple substring check, existing with-cross-build option fails this check

Example of affected recipe

ICU cross builds incorrectly because of this in some cases.

[franramirez688]

Hi @ovostrikov

Thanks for reporting it because, indeed, it's a bug. I'll open a PR fixing this for the next release.

[SpaceIm]

Something like this should be sufficient:

--- a/conan/tools/gnu/autotoolstoolchain.py
+++ b/conan/tools/gnu/autotoolstoolchain.py
@@ -186,8 +186,11 @@ class AutotoolsToolchain:
         configure_args.extend(self.configure_args)
         user_args_str = args_to_string(self.configure_args)
         for flag, var in (("host", self._host), ("build", self._build), ("target", self._target)):
-            if var and flag not in user_args_str:
-                configure_args.append('--{}={}'.format(flag, var))
+            if var:
+                arg = f"--{flag}="
+                if arg not in user_args_str:
+                    arg += var
+                    configure_args.append(arg)
 
         args = {"configure_args": args_to_string(configure_args),
                 "make_args":  args_to_string(self.make_args),