Ignore encoding errors when scanning. Closes #10571.

In Fortran and C++ all the bits we care about are in ASCII. 8-bit
characters can only occur in comments and string literals and we don't
parse those.

mesonbuild/scripts/depscan.py

@@ -62,7 +62,7 @@ class DependencyScanner:
     def scan_fortran_file(self, fname: str) -> None:
         fpath = pathlib.Path(fname)
         modules_in_this_file = set()
-        for line in fpath.read_text(encoding='utf-8').split('\n'):
+        for line in fpath.read_text(encoding='utf-8', errors='ignore').split('\n'):
             import_match = FORTRAN_USE_RE.match(line)
             export_match = FORTRAN_MODULE_RE.match(line)
             submodule_export_match = FORTRAN_SUBMOD_RE.match(line)
@@ -112,7 +112,7 @@ class DependencyScanner:
 
     def scan_cpp_file(self, fname: str) -> None:
         fpath = pathlib.Path(fname)
-        for line in fpath.read_text(encoding='utf-8').split('\n'):
+        for line in fpath.read_text(encoding='utf-8', errors='ignore').split('\n'):
             import_match = CPP_IMPORT_RE.match(line)
             export_match = CPP_EXPORT_RE.match(line)
             if import_match: