Print warning when linker arguments are passed to has_argument

has_argument and other similar methods of compiler objects only support
checking compiler flags. If they are used to check linker flags, the
results are very likely to be wrong and developers should be warned.

mesonbuild/compilers/c.py

@@ -804,6 +804,13 @@ class CCompiler(Compiler):
         return ['-pthread']
 
     def has_multi_arguments(self, args, env):
+        for arg in args:
+            if arg.startswith('-Wl,'):
+                mlog.warning('''{} looks like a linker argument, but has_argument
+and other similar methods only support checking compiler arguments.
+Using them to check linker arguments are never supported, and results
+are likely to be wrong regardless of the compiler you are using.
+'''.format(arg))
         return self.compiles('int i;\n', env, extra_args=args)
 
 

mesonbuild/compilers/cpp.py

@@ -14,6 +14,7 @@
 
 import os.path
 
+from .. import mlog
 from .. import coredata
 from ..mesonlib import version_compare
 
@@ -174,6 +175,13 @@ class IntelCPPCompiler(IntelCompiler, CPPCompiler):
         return []
 
     def has_multi_arguments(self, args, env):
+        for arg in args:
+            if arg.startswith('-Wl,'):
+                mlog.warning('''{} looks like a linker argument, but has_argument
+and other similar methods only support checking compiler arguments.
+Using them to check linker arguments are never supported, and results
+are likely to be wrong regardless of the compiler you are using.
+'''.format(arg))
         return super().has_multi_arguments(args + ['-diag-error', '10006'], env)