diff options
| -rw-r--r-- | llvm/lib/MC/WasmObjectWriter.cpp | 8 | ||||
| -rw-r--r-- | llvm/test/MC/WebAssembly/null-output.s | 10 |
2 files changed, 17 insertions, 1 deletions
diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp index d0ffe7c4a40..83ac9a44dc4 100644 --- a/llvm/lib/MC/WasmObjectWriter.cpp +++ b/llvm/lib/MC/WasmObjectWriter.cpp @@ -398,7 +398,13 @@ void WasmObjectWriter::startCustomSection(SectionBookkeeping &Section, // Now that the section is complete and we know how big it is, patch up the // section size field at the start of the section. void WasmObjectWriter::endSection(SectionBookkeeping &Section) { - uint64_t Size = W.OS.tell() - Section.PayloadOffset; + uint64_t Size = W.OS.tell(); + // /dev/null doesn't support seek/tell and can report offset of 0. + // Simply skip this patching in that case. + if (!Size) + return; + + Size -= Section.PayloadOffset; if (uint32_t(Size) != Size) report_fatal_error("section size does not fit in a uint32_t"); diff --git a/llvm/test/MC/WebAssembly/null-output.s b/llvm/test/MC/WebAssembly/null-output.s new file mode 100644 index 00000000000..a25d095e0cb --- /dev/null +++ b/llvm/test/MC/WebAssembly/null-output.s @@ -0,0 +1,10 @@ +# RUN: llvm-mc -triple=wasm32-unknown-unknown -filetype=obj -o /dev/null < %s + + .text + .section .text.main,"",@ + .type main,@function +main: + .functype main (i32, i32) -> (i32) + end_function +.Lfunc_end0: + .size main, .Lfunc_end0-main |
