Commit 4b1712f7 authored by Tom Stellard's avatar Tom Stellard
Browse files

Merging r352806: 

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r352806 | sbc | 2019-01-31 14:38:22 -0800 (Thu, 31 Jan 2019) | 5 lines

[WebAssembly] MC: Fix for outputing wasm object to /dev/null

Subscribers: dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D57479
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llvm-svn: 360949
parent 05288f50

llvm/lib/MC/WasmObjectWriter.cpp

+7 −1
Original line number Diff line number Diff line
@@ -368,7 +368,13 @@ 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");

llvm/test/MC/WebAssembly/null-output.s

0 → 100644
+10 −0
Original line number Diff line number Diff line 
# 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