<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/146837>146837</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
[clang][PowerPC] Clang links against host `/usr/lib32` when targeting `powerpc-linux-gnu` (but not `powerpc64-linux-gnu`)
</td>
</tr>
<tr>
<th>Labels</th>
<td>
clang
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
venkyqz
</td>
</tr>
</table>
<pre>
## Environment
| Category | Detail |
| --- | --- |
| **OS** | Ubuntu 22.04 |
| **Architecture** | x86_64 host |
| **Clang Versions** | 11 – 20 (tested: 11, 13, 15, 17, 19, 20.1.6) |
| **Target triple** | `powerpc-linux-gnu` |
| **Clang build** | Release |
## Summary
- Clang incorrectly links host's `/usr/lib32/Scrt1.o` when compiling for `--target=powerpc-linux-gnu` on `x86_64` Ubuntu systems, despite the correct cross toolchain being installed under `/usr/powerpc-linux-gnu`.
This causes linker errors due to a mismatched ELF format. This issue does **not** occur for `--target=powerpc64-linux-gnu` under identical environments (with dependencies `gcc-powerpc64-linux-gnu`, `g++-powerpc64-linux-gnu`, `binutils-powerpc64-linux-gnu` and `libc6-dev-ppc64-cross` installed with `apt` as well).
## Reproduce
- **File: `hello.c`**
```c
#include <stdio.h>
int main() {
printf("Hello PowerPC!\\n");
return 0;
}
```
- **Install dependency**
```bash
root@f806c162d501:/test# apt-get install gcc-powerpc-linux-gnu g++-powerpc-linux-gnu binutils-powerpc-linux-gnu libc6-dev-powerpc-cross
```
- **Broken command**
```bash
root@f806c162d501:/test# clang-20 --target=powerpc-linux-gnu -o hello-ppc hello.c
```
- **Output: Failed**
```bash
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/Scrt1.o: relocations in generic ELF (EM: 3)
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/Scrt1.o: relocations in generic ELF (EM: 3)
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/Scrt1.o: error adding symbols: file in wrong format
```
- **Verbose Output**
```bash
root@f806c162d501:/test# clang-20 -v --target=powerpc-linux-gnu -o hello-ppc hello.c
clang version 20.1.7
Target: powerpc-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/bin
Found candidate GCC installation: /usr/lib/gcc-cross/powerpc-linux-gnu/11
Found candidate GCC installation: /usr/lib/gcc-cross/powerpc64-linux-gnu/11
Selected GCC installation: /usr/lib/gcc-cross/powerpc-linux-gnu/11
Candidate multilib: .;@m32
Selected multilib: .;@m32
"/usr/local/bin/clang-20" -cc1 -triple powerpc-unknown-linux-gnu -emit-obj -dumpdir hello-ppc- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name hello.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu ppc -mfloat-abi hard -debugger-tuning=gdb -fdebug-compilation-dir=/test -v -fcoverage-compilation-dir=/test -resource-dir /usr/local/lib/clang/20 -internal-isystem /usr/local/lib/clang/20/include/ppc_wrappers -internal-isystem /usr/local/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/hello-ac8ddb.o -x c hello.c
clang -cc1 version 20.1.7 based upon LLVM 20.1.7 default target x86_64-unknown-linux-gnu
ignoring nonexistent directory "/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/local/lib/clang/20/include/ppc_wrappers
/usr/local/lib/clang/20/include
/usr/local/include
/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/include
/usr/include
End of search list.
"/usr/bin/powerpc-linux-gnu-ld" -z relro --hash-style=gnu --eh-frame-hdr -m elf32ppclinux -pie -dynamic-linker /lib/ld.so.1 -o hello-ppc /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/Scrt1.o /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/crti.o /usr/lib/gcc-cross/powerpc-linux-gnu/11/crtbeginS.o -L/usr/lib/gcc-cross/powerpc-linux-gnu/11 -L/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32 -L/lib/powerpc-linux-gnu -L/lib/../lib32 -L/usr/lib/powerpc-linux-gnu -L/usr/lib/../lib32 -L/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/lib -L/lib -L/usr/lib /tmp/hello-ac8ddb.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc-cross/powerpc-linux-gnu/11/crtendS.o /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32/crtn.o
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../**lib32/Scrt1.o**: relocations in generic ELF (EM: 3)
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../**lib32/Scrt1.o**: relocations in generic ELF (EM: 3)
/usr/bin/powerpc-linux-gnu-ld: /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../**lib32/Scrt1.o**: error adding symbols: file in wrong format
clang-20: error: linker command failed with exit code 1 (use -v to see invocation)
```
## Expected Behavior
- Clang should use the correct startup objects from:
```bash
/usr/powerpc-linux-gnu/lib/Scrt1.o
```
- and **not** pick up unrelated host files from:
```bash
/usr/lib32/Scrt1.o
```
## Observation
- Despite `-target=powerpc-linux-gnu`, Clang chooses `/usr/lib32/Scrt1.o` from the host.
- Resulting in a linker error due to incompatible ELF class.
- This behavior is **not** observed when targeting:
- `powerpc64-linux-gnu`
- `aarch64-linux-gnu`
- `arm-linux-gnueabi`
- etc.
## Workarounds
- **Specify targer specific `Scrt1.o` file**
```bash
root@f806c162d501:/test# clang-20 -v --target=powerpc-linux-gnu -nostdlib /usr/powerpc-linux-gnu/lib/crt1.o -L/usr/powerpc-linux-gnu/lib -lc /usr/powerpc-linux-gnu/lib/crtn.o -o hello-ppc hello.c
```
- **Output (Verbose): Success**
```bash
root@f806c162d501:/test# clang-20 -v --target=powerpc-linux-gnu -nostdlib /usr/powerpc-linux-gnu/lib/crt1.o -L/usr/powerpc-linux-gnu/lib -lc /usr/powerpc-linux-gnu/lib/crtn.o -o hello-ppc hello.c
clang version 20.1.7
Target: powerpc-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/bin
Found candidate GCC installation: /usr/lib/gcc-cross/powerpc-linux-gnu/11
Found candidate GCC installation: /usr/lib/gcc-cross/powerpc64-linux-gnu/11
Selected GCC installation: /usr/lib/gcc-cross/powerpc-linux-gnu/11
Candidate multilib: .;@m32
Selected multilib: .;@m32
"/usr/local/bin/clang-20" -cc1 -triple powerpc-unknown-linux-gnu -emit-obj -dumpdir hello-ppc- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name hello.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu ppc -mfloat-abi hard -debugger-tuning=gdb -fdebug-compilation-dir=/test -v -fcoverage-compilation-dir=/test -resource-dir /usr/local/lib/clang/20 -internal-isystem /usr/local/lib/clang/20/include/ppc_wrappers -internal-isystem /usr/local/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -ferror-limit 19 -fno-signed-char -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/hello-d0a071.o -x c hello.c
clang -cc1 version 20.1.7 based upon LLVM 20.1.7 default target x86_64-unknown-linux-gnu
ignoring nonexistent directory "/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/local/lib/clang/20/include/ppc_wrappers
/usr/local/lib/clang/20/include
/usr/local/include
/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/include
/usr/include
End of search list.
"/usr/bin/powerpc-linux-gnu-ld" -z relro --hash-style=gnu --eh-frame-hdr -m elf32ppclinux -pie -dynamic-linker /lib/ld.so.1 -o hello-ppc -L/usr/powerpc-linux-gnu/lib -L/usr/lib/gcc-cross/powerpc-linux-gnu/11 -L/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../lib32 -L/lib/powerpc-linux-gnu -L/lib/../lib32 -L/usr/lib/powerpc-linux-gnu -L/usr/lib/../lib32 -L/usr/lib/gcc-cross/powerpc-linux-gnu/11/../../../../powerpc-linux-gnu/lib -L/lib -L/usr/lib /usr/powerpc-linux-gnu/lib/crt1.o -lc /usr/powerpc-linux-gnu/lib/crtn.o /tmp/hello-d0a071.o
```
## Fix Advice
Clang should:
- Prefer `$sysroot/$triple/lib` and similar over host `/usr/lib32` if `-target` is specified.
- Match the behavior of GCC and avoid falling back to host paths unless explicitly instructed.
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzsGl1PK7fy15iXkaONNwnJAw8hIW2lc9Tq0Hv6iLz2bNbFa--1vQH666_s3cAGEsr5qu69QkKB2DPj8XzPYO692hrECzK9JNP1GW9DZd3FDs3tw7__OiusfLggLCcshyuzU86aGk0g2TL-nK9gxQNurXuA-GWNgSsd_-x3KaUw-N2vErYkbPnrdfc7AfyraE1ogbFRNnkBuXSiUgFFaB0OcO7ns5vZBCrrwwuUleZmC5_ReWWNHyCNx0CuGJlnZJEDy4CweUAfUJJ8CeMxYSsY5-lzmj7P0-cifrJsNB7NCFu8OO137rYYIDjV6CGHZJY19g5dI6hWpr2nW9OSWXaC26JVWg6wP6FG7nEPnS17PVy3dc3dQ7dGoUNWRljnUAT9AFqZW5_kQti5j1wQtmm9I2yjVZEzwjbXwoXxyEZm7io0IGzdKK3MFkrrIgalIV2K5OujV7AmQnUqiN97BfoHH7D2UVwSfaMCQqgQet5AOOs9BGu1qLgyUKBKvPvAtUYJrZHoDhg-dviIZMvfK-VB8NajT_dFB-icdR5kixAscKiVr3kQFUq4-rCJF6t5GEHCVN63CNKi71VgbOhFb4Vo3WkxzCaHguhYVhJNUIJrwCcvibTndypUILFBI9EIhUkfWyHocXpRchGAsEvCLl8HKpRpg9L-BBRwIyOYVoWYUYk72iSYpIS4_yT3xCSZZbwJCdHDHWpN2GJ0YHmfsHFWtgL3tteJbKM0Rvchs6xCre1IJB7jVo8-y7of0dFSRuhWIpB85YNUdlSR_IpkS2UC1FwZwuadm12SbAkA0DhlQpmW2c_xCPgtXvm3FWFjMl2R6coQxghbkHyP4jC0zkDWrZDz9ZCPQ_5_6eTwpKWHo8wX3FckWzprA5lk5TybifGMyWk2JvmSsE2MI1FKvAk0hoNevDBQ9pN-4JmGBzvP1TrYGqiy3-uUefJql87edu5dcyO_6VoixhnKMngtNAC1kGwg2hrsreEke7-2oWlDtJ0NVxpfZfAxJBTRQF4GBqpTDB-GOsI2UfidjI7FEraJIX8zGr38eB4p8yU41FbwEDMKKANbNOiUSMGFsPnVxwiTRyN8Z_YLmU2hG7iUMR34h7qw2sf1UmmM3N8526WmmofT1vQZXWE9Qm9V38fYd19u70CyZSIAu64A6UqH85i2ekpL2JNqza2xd2YgupjcHHIJtZWoO1iv7km2D1Qo18odasQKrnsFZsuNbY0EwY1UkgeEn1arfTBKBvF1yvxedA-yVE_5GjWKgPK7sbp6ZLJudVARM1_CKCaDSVbnbHjmSQhIOeWIiNlmbx-EMaBCjIF2xd9ptQLFWgVqiz-ByrZupHJPlkOBSuV5oZGWDhGo0Mgd5T7QAkvrkBZc3KKRT3Ba72q6Q6dKhS4tC-4k3XHdIjW8Rg805lIafSgtPJonrZ-CA01GBo0SQBslqMYdamDdF-VpoxBoXTpeI22sMgEdydcxrdGy5qGi6JyxQMuyocKa4LiIjmIN0NJY6qLJKLOlERZoLazxwbUiWEe5VjyWb7RszZ0ykoZ4MU_yNYPe5ahoWoieRetSWx4oLxRU3EU5YNFut-hoaI0yW5Kvt7IAWqZ12tWz3Q1ldJZ179zJoUthd-j4Fl-Dc-ht6wTG9Zee1tliMgPCNjFQJNkYrqnqiuC_xyFs01dC0ZQbcXPneNOg899G7C3YbwH9tih_DPjlqXgf_xDD098E1LH4CFqmBEK1qlWA8aKzvdTYSioq7oCWW9MK2sdjkq8nIzYaAy39rWqolY6KCsUtVYZu6zJZiLaOSsW3xvqgRDRTLqXzagt0fXPz02p18_Py89XN-o_lpw27WW1-uVlefyT5ehxzQrSiuiFs07k4F3Mpi5EFeg_DsqjLEimAHKYKKLiP_VBjDXz48PnjflliyVsdoHOPvgU-mkPU1lgX06mxBu-VD2gCSBXbsNSup9D2aH7sWWHO2ChqkYFH7kQFPnAXPFToYqX_ooqPwPnVSeBvcIUvxT4GfnTvh1n3wTFPa1dGgi33ItLKh9HzFPNK-RXTzF-xpnMWKK24r6gPD7HtWqfcQrGiXZCupANaA-oyZ00jEhXowrh8MLxWiXLslx-loOXI29H4sJb5QdXed6crXFBfSVa4UOBWmevomB--mMLX4Lx2mY5eR-lIofm0-RxlyMIJxCHIa-jf1SG0Kh7ZfnbU6QCpt0IApdxTgyhRdis3Hig19mBZvB34K60Djbz-MSZrRvafb7y6juh5-9W1Sf_VHeP_K-Nf2PY-Nh171PhHH8z7CQ-UaY7SDfTwXgUQViKMoyBaj7H6DRY8RvK7Xmi9ZA576v3M_77pmqRLrPhOWXc4dfaVbbWESHk45k0FQNuALf5EETyUztZ92fDKXOdECBkI7kjnn2aczya4jRK30DbQGoeaR-7T_wiiVN_Ky3OVnZLPr4VHt-vE2HO07ufeZJa9PkMnbNWLUVTWevzbSX1kPck5XmeUDvuEPnavaYgO_GASvh-EKxObHB5UoTH5hNDc-w49zcKLXrWgjgzD0_2iQVVo-qozdVvLfsxKB__keD6lHkDwWPW8tu_qpz3khRruYxCHc-g_rLvlqbX0hxOg6waFKh86Rh349FWJeMJQjmr_X5ofPh2KzYPs893fWXlfIA0S5cmkqsUbCZpI8CtGsjFe9OO0NFVfwnUrBHr_Lrf3yd77ZO99svc-2Xuf7L1P9iyVGc_Ox--TvffJ3v_MZO8thdL7NOyfnoa9tcr9ohL2RLA62c5u1D0s5U7tX_gMu_zHppnCbw7L_TutiX_wqfBnG8Im-ydwiY3-CZJXtdLcQczM_Wu9F33uLANVDlvmuOD3DRzKrl39yIOoUgf82LPaMlWW8Ry-s0pCyXV6xxbLqtj-pgMbHioPrdHoPeB9o5VQQT-kgjTWLChHZ_Iil4t8wc_wYnw-HU_zfJbPz6qLbJ7NJ-cCZ-eFXMwynCw4m0_LSb5ANi_G2Zm6YBmbZudZni2y8_F8tOB8Js5Zmc0Xc5aVJZlkWHOlR7GyG1m3PUvPzy7Gk9k8Pz_TvEDt0wNMxvrQx8h0feYuUilYtFtPJlkMLP6JRFBBp1ebHcZ0TaaX-0dR03U_WOheAvItjxd9RfaH3f3pd4tsXrQBjA2vdP1scdY6fVGF0Piu_YuepELVFiNh63is3u1_0cbZP1FE60kyiZ7Wi2V3wf4TAAD__zKuhfo">