libexpr: make .debug_gdb_scripts aligned

This avoids mangling debug gdb scripts and breaking them resulting in no
script loading at all.

Change-Id: Ib5e7034c37a1e41d1a1c9bd8442b8b8b8758e350
Signed-off-by: Raito Bezarius <raito@lix.systems>

lix/libexpr/eval.cc

@@ -46,7 +46,7 @@
 // Ignore all internal signals boehm uses for parallel marking
 // FIXME: Find out how to do this with LLDB for macOS!
 #ifndef __APPLE__
-[[gnu::section(".debug_gdb_scripts"), gnu::used]]
+[[gnu::section(".debug_gdb_scripts"), gnu::used, gnu::aligned(1)]]
 // TODO: We should use `SECTION_SCRIPT_ID_PYTHON_TEXT` from
 // `<gdb/section-scripts.h>` instead of hardcoding 4.
 // But why isn't this header exported by GDB?

lix/libexpr/value.cc

@@ -82,7 +82,7 @@ void Value::mkPath(const SourcePath & path)
 }
 
 #ifndef __APPLE__
-[[gnu::section(".debug_gdb_scripts"), gnu::used]]
+[[gnu::section(".debug_gdb_scripts"), gnu::used, gnu::aligned(1)]]
 static const char printer_script[] =
     "\4"
     R"(lix-value-printer