rust: Add cflag checks against -xc++ and -std.
If -x c++ is passed through a modules cflags, it will be overridden by a
-x c and -std flag added by the build system if the extension is not
.hpp/.hh and cpp_std is not set. This leads to confusing behavior.
Instead, add a helpful error message to guide developers towards the
correct way to specify when a header is a C++ header and which std
version should be used.
Bug: 171011490
Test: m nothing
Change-Id: I7e7cba504798d47ce1c753ba8699d7475a95095b
diff --git a/rust/bindgen.go b/rust/bindgen.go
index ac33ff7..46d4acb 100644
--- a/rust/bindgen.go
+++ b/rust/bindgen.go
@@ -150,6 +150,18 @@
esc := proptools.NinjaAndShellEscapeList
+ // Filter out invalid cflags
+ for _, flag := range b.ClangProperties.Cflags {
+ if flag == "-x c++" || flag == "-xc++" {
+ ctx.PropertyErrorf("cflags",
+ "-x c++ should not be specified in cflags; setting cpp_std specifies this is a C++ header, or change the file extension to '.hpp' or '.hh'")
+ }
+ if strings.HasPrefix(flag, "-std=") {
+ ctx.PropertyErrorf("cflags",
+ "-std should not be specified in cflags; instead use c_std or cpp_std")
+ }
+ }
+
// Module defined clang flags and include paths
cflags = append(cflags, esc(b.ClangProperties.Cflags)...)
for _, include := range b.ClangProperties.Local_include_dirs {