BUG: parse shell escaping in extra_compile_args and extra_link_args

Thanks to a change in exec_command, these strings are no longer passed onto the shell.
Since config files do not support list values, our best bet is to perform shell-splitting immediately.

This brings the behavior back in line a little to how it was before.

On windows systems, the behavior has changed. Previously it was treated as a single argument unless it contained quotes, resulting in the following weird behavior:

    # passes as one argument, preserving spaces
    extra_link_args=-Wl,rpath=A:/path/with spaces
    # passes as two arguments, preserving spaces
    extra_link_args="-Wl,rpath=A:\path\with spaces" -lgfortran
    # passes as one long quoted argument (surprising and undesirable)
    extra_link_args=-Wl,rpath=A:\path\without_spaces -lgfortran

Now it behaves as windows escaping via subprocess (but _not_ via cmd) normally would:

    # Passed as two separate arguments (probably not as intended, but should be expected)
    extra_link_args=-Wl,rpath=A:/path/with spaces
    # passes as two arguments, preserving spaces
    extra_link_args="-Wl,rpath=A:\path\with spaces" -lgfortran
    # passes as two arguments
    extra_link_args=-Wl,rpath=A:\path\without_spaces -lgfortran

Fixes gh-12659

1 files changed, 2 insertions, 2 deletions

diff --git a/site.cfg.example b/site.cfg.example
index 48b17fbdf..f5c9ca227 100644
--- a/site.cfg.example
+++ b/site.cfg.example
@@ -64,14 +64,14 @@
 #
 #   extra_compile_args
 #       Add additional arguments to the compilation of sources.
-#       Simple variable with no parsing done. 
+#       Split into arguments in a platform-appropriate way.
 #       Provide a single line with all complete flags.
 #           extra_compile_args = -g -ftree-vectorize
 #
 #   extra_link_args
 #       Add additional arguments when libraries/executables
 #       are linked.
-#       Simple variable with no parsing done. 
+#       Split into arguments in a platform-appropriate way.
 #       Provide a single line with all complete flags.
 #           extra_link_args = -lgfortran
 #