CompilerArgs: Allow calling to_native() multiple times

Add a keyword argument to to_native() to operate on a copy so that we
can call it multiple times instead of modifying the original compiler
args while iterating.

This is used in the unit test, and might be used in Meson at some
point too.

1 files changed, 9 insertions, 5 deletions

diff --git a/mesonbuild/compilers/compilers.py b/mesonbuild/compilers/compilers.py
index 5af4b5d..95f937d 100644
--- a/mesonbuild/compilers/compilers.py
+++ b/mesonbuild/compilers/compilers.py
@@ -602,16 +602,20 @@ class CompilerArgs(list):
             return True
         return False
 
-    def to_native(self):
+    def to_native(self, copy=False):
         # Check if we need to add --start/end-group for circular dependencies
         # between static libraries, and for recursively searching for symbols
         # needed by static libraries that are provided by object files or
         # shared libraries.
+        if copy:
+            new = self.copy()
+        else:
+            new = self
         if get_compiler_uses_gnuld(self.compiler):
             global soregex
             group_start = -1
             group_end = -1
-            for i, each in enumerate(self):
+            for i, each in enumerate(new):
                 if not each.startswith('-l') and not each.endswith('.a') and \
                    not soregex.match(each):
                     continue
@@ -621,9 +625,9 @@ class CompilerArgs(list):
                     group_start = i
             if group_start >= 0:
                 # Last occurrence of a library
-                self.insert(group_end + 1, '-Wl,--end-group')
-                self.insert(group_start, '-Wl,--start-group')
-        return self.compiler.unix_args_to_native(self)
+                new.insert(group_end + 1, '-Wl,--end-group')
+                new.insert(group_start, '-Wl,--start-group')
+        return self.compiler.unix_args_to_native(new)
 
     def append_direct(self, arg):
         '''