diff --git a/lld/test/wasm/lto/pic-empty.s b/lld/test/wasm/lto/pic-empty.s new file mode 100644 --- /dev/null +++ b/lld/test/wasm/lto/pic-empty.s @@ -0,0 +1,21 @@ +; Test that LTO objects with no function can still be linked as shared +; libraries. +; We had a bug where the mutable-globals feature was not being added +; so the linker-generated import of `__stack_pointer` (which is currently +; mandatory for ; shared libraries) was generating a linker error. +; See https://bugs.llvm.org/show_bug.cgi?id=52339 + +; RUN: llvm-as %s -o %t.o +; RUN: wasm-ld -lto-O2 --experimental-pic -shared --no-gc-sections --export=tls_int %t.o -o %t.so +; RUN: obj2yaml %t.so | FileCheck %s + +target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-f128:64-n32:64-S128-ni:1:10:20" +target triple = "wasm32-unknown-emscripten" + +@tls_int = dso_local thread_local global i32 99 + +; CHECK: - Type: CUSTOM +; CHECK: Name: target_features +; CHECK: Features: +; CHECK: - Prefix: USED +; CHECK: Name: mutable-globals diff --git a/lld/wasm/Writer.cpp b/lld/wasm/Writer.cpp --- a/lld/wasm/Writer.cpp +++ b/lld/wasm/Writer.cpp @@ -433,6 +433,13 @@ SmallSet &allowed = out.targetFeaturesSec->features; bool tlsUsed = false; + if (config->isPic) { + // This should not be necessary because all PIC objects should + // contain the mutable-globals feature. + // TODO(https://bugs.llvm.org/show_bug.cgi?id=52339) + allowed.insert("mutable-globals"); + } + // Only infer used features if user did not specify features bool inferFeatures = !config->features.hasValue();