On Fri, Mar 03, 2023 at 05:31:41PM +0000, Simon McVittie wrote: > # clang++-15 -c --target=wasi-wasm32 -ostddef-cpp.o stddef.cpp > # apt-get install --no-install-recommends libc++-15-dev > # clang++-15 -c --target=wasi-wasm32 -ostddef-cpp.o stddef.cpp > > Expected result: both clang++-15 calls succeed (stddef.h declares size_t) > > Actual result: the second clang++-15 call fails:
(Super helpful bug report, thanks!) As I mentioned in #1029010 just now, this is a regression from 14->15. Retracing the same steps with clang-14 & libc++-14-dev-wasm32, there are no errors and everything works as intended. Looking at the differences of the include paths between the two by passing -v to clang, one can see: /usr/include/wasm32-wasi/c++/v1 - /usr/lib/llvm-14/lib/clang/14.0.6/include + /usr/include/c++/v1 + /usr/lib/llvm-15/lib/clang/15.0.7/include /usr/local/include /usr/include/wasm32-wasi /usr/include i.e. /usr/include/c++/v1 (i.e. libc++-15-dev) is included in the include path only with clang-15. It shouldn't be. Looking at the interdiff of d/patches/wasm/wasm-sysroot-usr.diff[1] patch between llvm-toolchain 1:14.0.6-12 and 1:15.0.7-1, it looks line there are a few hunks that are missing. Specifically, it looks like the entire patching of the method WebAssembly::AddClangCXXStdlibIncludeArgs isn't happening anymore. One of these differences was exactly about this -- the comment says: // don't include the host architecture's headers in the search path Sylvestre, I think you did the 14->15 porting, right? Do you know/remember what happened there? Regards, Faidon 1: Note that the git tree also has d/patches/wasm-sysroot-usr.diff (and d/patches/wasm-compiler-rt-default.diff) which are earlier versions of this patch, now unused (not in d/patches/series). I think what happened was that the files were copied, instead of moved, to d/patches/wasm/. Here I am talking exclusively about the versions in d/patches/wasm/. It'd be good to cleanup this cruft to avoid further confusion.
