$ CONF=linux-x86-server-slowdebug make clean all
...
* For target buildjdk_hotspot_variant-server_libjvm_objs_compile.o:
/home/shade/trunks/jdk/src/hotspot/share/opto/compile.cpp: In member function 'void Compile::print_method(CompilerPhaseType, int, int)':
/home/shade/trunks/jdk/src/hotspot/share/opto/compile.cpp:4673:5: error: 'jio_snprintf' was not declared in this scope; did you mean 'vsnprintf'?
 4673 | jio_snprintf(output, sizeof(output), "%s:%d", CompilerPhaseTypeHelper::to_string(cpt), idx);
      | ^~~~~~~~~~~~
      | vsnprintf
/home/shade/trunks/jdk/src/hotspot/share/opto/compile.cpp:4675:5: error: 'jio_snprintf' was not declared in this scope; did you mean 'vsnprintf'?
 4675 | jio_snprintf(output, sizeof(output), "%s", CompilerPhaseTypeHelper::to_string(cpt));
      | ^~~~~~~~~~~~
      | vsnprintf


It is somewhat weird it only manifests on x86_32.

linux-x86-server-fastdebug fails as well.