Basic Block has trailing DbgRecords! #155030
Description
Termux Emscripten 4.0.13 with Clang 22.0.0git fails sometimes when using all of -Os -fexceotions -gsource-map and setjmp(), here with libpng related code. The error message is
Basic Block has trailing DbgRecords!
build log with backtrace :
clang dumps :
smaller reproducer:
/*
em++ -std=c++17 -Wall -pedantic -Wextra \
-Os -fexceptions -gsource-map -c bug.c */
#include <setjmp.h>
extern void *create(void);
extern void destroy(void *p);
int bug(void)
{
jmp_buf jmpbuf;
void *file = create();
if (! file)
return 1;
void *png = create();
if (! png)
return 2;
void *info = create();
if (! info)
{
destroy(png);
destroy(file);
return 3;
}
if (setjmp(jmpbuf))
{
destroy(info);
destroy(png);
destroy(file);
return 4;
}
destroy(file);
return 0;
}Basic Block has trailing DbgRecords!
label %entry.split
Basic Block has trailing DbgRecords!
label %if.end
Basic Block has trailing DbgRecords!
label %if.end4
Basic Block has trailing DbgRecords!
label %if.end
Basic Block has trailing DbgRecords!
label %if.end4
fatal error: error in backend: Broken
module found, compilation aborted!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: /data/data/com.termux/files/usr/opt/emscripten-llvm/bin/clang++ -target wasm32-unknown-emscripten -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-cxx-exceptions -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=/data/data/com.termux/files/usr/opt/emscripten/cache/sysroot -DEMSCRIPTEN -Xclang -iwithsysroot/include/fakesdl -Xclang -iwithsysroot/include/compat -std=c++17 -Wall -pedantic -Wextra -Os -fexceptions -g -c bug.cc
1. <eof> parser at end of file
2. Code generation
clang++: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 22.0.0git
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /data/data/com.termux/files/usr/opt/emscripten-llvm/bin
Build config: +assertions
clang++: note: diagnostic msg:
********************
PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang++: note: diagnostic msg: /data/data/com.termux/files/usr/tmp/bug-603d53.cpp
clang++: note: diagnostic msg: /data/data/com.termux/files/usr/tmp/bug-603d53.sh
clang++: note: diagnostic msg:
********************