The jit testsuite was showing numerous segfaults and fatal errors for trunk on aarch64; typically on the 2nd iteration of each test, with errors like: test-volatile.c.exe: fatal error: pass ‘rnreg’ not found but is referenced by new pass ‘whole-program’ where the new pass' name varies, and can be bogus, e.g.: test-nested-loops.c.exe: fatal error: pass 'rnreg' not found but is referenced by new pass '/tmp/libgccjit-FMb7g3/fake.c'
This is a regression relative to gcc 5. The root cause is that aarch64_register_fma_steering builds and registers an "fma_steering" pass after "rnreg", but the struct register_pass_info containing the arguments to register_pass is marked "static". Hence after the 1st iteration, the pointer to the pass isn't touched, and we have a use-after-free of the 1st iteration's pass_fma_steering. The attached patch removes the "static" from the relevant local, so that the pass pointer is updated before each call to register_pass. With this patch, the jit testsuite runs successfully (8514 passes) on gcc113 (aarch64-unknown-linux-gnu). I used grep to see if there were any other "static struct register_pass_info" in the code, and there's one in the mips backend, so I did the same change there (untested). Bootstrap on aarch64 in progress; I don't have mips handy. OK for trunk if it passes? gcc/ChangeLog: * config/aarch64/cortex-a57-fma-steering.c (aarch64_register_fma_steering): Remove "static" from arguments to register_pass. * config/mips/frame-header-opt.c (mips_register_frame_header_opt): Likewise. --- gcc/config/aarch64/cortex-a57-fma-steering.c | 2 +- gcc/config/mips/frame-header-opt.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/gcc/config/aarch64/cortex-a57-fma-steering.c b/gcc/config/aarch64/cortex-a57-fma-steering.c index 5d2ec87..21159fe 100644 --- a/gcc/config/aarch64/cortex-a57-fma-steering.c +++ b/gcc/config/aarch64/cortex-a57-fma-steering.c @@ -1082,7 +1082,7 @@ aarch64_register_fma_steering () { opt_pass *pass_fma_steering = make_pass_fma_steering (g); - static struct register_pass_info fma_steering_info + struct register_pass_info fma_steering_info = { pass_fma_steering, "rnreg", 1, PASS_POS_INSERT_AFTER }; register_pass (&fma_steering_info); diff --git a/gcc/config/mips/frame-header-opt.c b/gcc/config/mips/frame-header-opt.c index cc51577..9c3674a 100644 --- a/gcc/config/mips/frame-header-opt.c +++ b/gcc/config/mips/frame-header-opt.c @@ -98,7 +98,7 @@ void mips_register_frame_header_opt (void) { opt_pass *p = make_pass_ipa_frame_header_opt (g); - static struct register_pass_info f = + struct register_pass_info f = {p, "comdats", 1, PASS_POS_INSERT_AFTER }; register_pass (&f); } -- 1.8.5.3