[Comgr][test] Add -nostdinc++ to compile_hip_with_libcxx_test#2444
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[Comgr][test] Add -nostdinc++ to compile_hip_with_libcxx_test#2444lamb-j wants to merge 3 commits into
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## Summary Disable `compile_hip_with_libcxx_test` -- it currently fails on systems with system libstdc++ at clang's default search path (manylinux/RHEL with gcc-toolset). Root cause and proper fix tracked in #2444 and #2445; will be re-enabled by #2444 once that lands. Co-authored-by: Claude <noreply@anthropic.com>
The test claims to verify that embedded libc++ headers work with HIP
compilation, but only passes -nogpuinc -- which disables GPU-specific
includes but leaves system C++ header lookup enabled.
On systems with system libstdc++ installed at clang's default search
path (manylinux/RHEL with gcc-toolset), clang resolves <tuple> to the
system header, which transitively pulls in <stddef.h> from
cxxabi_init_exception.h. That stddef.h resolves to clang's libc++
stddef.h, which does #include_next <stddef.h>. Under HIP
--offload-device-only mode there is no next stddef.h on the device
include path, so the chain breaks:
In file included from .../cxxabi_init_exception.h:38:
include/c++/v1/stddef.h:39:15: fatal error: 'stddef.h' file not found
39 | #include_next <stddef.h>
This is a real coverage gap in the test (it isn't actually verifying
the embedded headers in environments that have system libstdc++) and a
silent failure mode of the underlying COMPILE_SOURCE_WITH_DEVICE_LIBS_TO_BC
action (the embedded-fallback design at comgr-compiler.cpp:1211-1216
assumes any present system libstdc++ works on its own; under HIP device
mode that assumption is broken on RHEL/manylinux).
Add -nostdinc++ to the test so it actually isolates the embedded
headers, which is what the test name and comments claim.
A separate issue tracks the broader design question of whether comgr
should auto-inject -nostdinc++ with -nogpuinc, or promote the embedded
libc++ from -idirafter to -isystem.
Co-Authored-By: Claude <noreply@anthropic.com>
The full root-cause chain lives in issue #2445; the test only needs to explain why -nostdinc++ is here. Co-Authored-By: Claude <noreply@anthropic.com>
Reverts the disable from #2447 now that the underlying issue (the test not passing -nostdinc++) is fixed by this PR. Co-Authored-By: Claude <noreply@anthropic.com>
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Summary
compile_hip_with_libcxx_testclaims to verify that embedded libc++ headers work with HIP compilation, but only passes-nogpuinc-- which disables GPU-specific includes but leaves system C++ header lookup enabled. On systems with system libstdc++ installed at clang's default search path (manylinux / RHEL with gcc-toolset), the test silently exercises system libstdc++, not the embedded headers.Worse, on RHEL/manylinux specifically, the test fails at
amd_comgr_do_action():Root cause
#include <tuple>.<tuple>to system gcc-8 libstdc++ (/usr/lib/gcc/.../include/c++/8/tuple) because the embedded libc++ is injected at-idirafterpriority (comgr-compiler.cpp:1211-1216).<exception_ptr.h>-><cxxabi_init_exception.h>-><stddef.h>.stddef.hresolves to libc++'sinclude/c++/v1/stddef.h(VFS-mapped to clang's resource dir).#include_next <stddef.h>-- but under HIP--offload-device-onlywith-nogpuinc, no further stddef.h is available on the device include path. Chain breaks.Fix
Add
-nostdinc++to the test's compile options so clang only finds the embedded headers, which is what the test name and comments claim to verify. Tested in the manylinux container -- test now passes.This was caught by the new SPIRV CI workflow on
ROCm/SPIRV-LLVM-TranslatorPR #178, which builds Comgr inside the manylinux container that other compiler-stack workflows use.Follow-up
Filed a separate issue tracking the broader design question (whether comgr should auto-inject
-nostdinc++with-nogpuinc, or promote the embedded libc++ from-idirafterto-isystemso users don't have to opt in explicitly).