add docs and error hints when a Call should be a CallImport (#1081)

* add docs and error hints when a Call should be a CallImport

* fix binaryen API docs in docs/

1 files changed, 3 insertions, 0 deletions

diff --git a/src/binaryen-c.h b/src/binaryen-c.h
index 90c7795f0..f37bcf085 100644
--- a/src/binaryen-c.h
+++ b/src/binaryen-c.h
@@ -281,6 +281,9 @@ BinaryenExpressionRef BinaryenSwitch(BinaryenModuleRef module, const char **name
 //                   type returned by the function being called, as that
 //                   function might not have been created yet, so we don't
 //                   know what it is.
+//                   Also note that WebAssembly does not differentiate
+//                   between Call and CallImport, but Binaryen does, so you
+//                   must use CallImport if calling an import, and vice versa.
 BinaryenExpressionRef BinaryenCall(BinaryenModuleRef module, const char *target, BinaryenExpressionRef* operands, BinaryenIndex numOperands, BinaryenType returnType);
 BinaryenExpressionRef BinaryenCallImport(BinaryenModuleRef module, const char *target, BinaryenExpressionRef* operands, BinaryenIndex numOperands, BinaryenType returnType);
 BinaryenExpressionRef BinaryenCallIndirect(BinaryenModuleRef module, BinaryenExpressionRef target, BinaryenExpressionRef* operands, BinaryenIndex numOperands, const char* type);