[MC] Error on a .zerofill directive in a non-virtual section

On darwin, all virtual sections have zerofill type, and having a
.zerofill directive in a non-virtual section is not allowed. Instead of
asserting, show a nicer error.

In order to use the equivalent of .zerofill in a non-virtual section,
the usage of .zero of .space is required.

This patch replaces the assert with an error.

Differential Revision: https://reviews.llvm.org/D48517

llvm-svn: 336127

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/MC/MCWasmStreamer.cpp b/llvm/lib/MC/MCWasmStreamer.cpp
index c950ac778ea..0e593221404 100644
--- a/llvm/lib/MC/MCWasmStreamer.cpp
+++ b/llvm/lib/MC/MCWasmStreamer.cpp
@@ -215,7 +215,8 @@ void MCWasmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
 }
 
 void MCWasmStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
-                                  uint64_t Size, unsigned ByteAlignment) {
+                                  uint64_t Size, unsigned ByteAlignment,
+                                  SMLoc Loc) {
   llvm_unreachable("Wasm doesn't support this directive");
 }