https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112587
Bug ID: 112587
Summary: -save-temps with p1689 dep output causes null ptr
dereference
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nickbegg at gmail dot com
Target Milestone: ---
Whilst debugging a separate bug with a trivial module, GCC crashes with a null
ptr dereference. I have --save-temps on.
The problem seems to start here:
gcc/c-family/c-opts.cc:1340
fatal_error (input_location, "%<-MF%> and %<-fdeps-file=%> cannot share an
output file %s: %m", fdeps_file);
The cc1plus process looks like it's not invoked with -fdeps-file, and thus
fdeps_file is null. Printing this diagnostic causes a crash. It seems to crash
before a bug report is written out.
This is the version -
GNU C++23 (GCC) version 14.0.0 20231117 (experimental) (x86_64-pc-linux-gnu)
(git rev ba3f5b8465ef7b278ea33ff94cd85b9638058635)
This is the cmdline used to launch gcc (launched from cmake/ninja) -
/home/nick/gcc-trunk-debug-inst/bin/g++ -D_GLIBCXX_ASSERTIONS -D_GLIBCXX_DEBUG
-std=gnu++23 -Wall -Wextra -v -freport-bug -save-temps -MD -MT
CMakeFiles/moduleMin.dir/modA.mpp.o -MF CMakeFiles/moduleMin.dir/modA.mpp.o.d
-fmodules-ts -fmodule-mapper=CMakeFiles/moduleMin.dir/modA.mpp.o.modmap -MD
-fdeps-format=p1689r5 -x c++ -o CMakeFiles/moduleMin.dir/modA.mpp.o -c
/home/nick/src/moduleMin/modA.mpp
... and the cmdline to launch cc1plus which crashes -
/home/nick/gcc-trunk-debug-inst/libexec/gcc/x86_64-pc-linux-gnu/14.0.0/cc1plus
-fpreprocessed CMakeFiles/moduleMin.dir/modA.mpp.ii -quiet -dumpdir
CMakeFiles/moduleMin.dir/ -dumpbase modA.mpp.mpp -dumpbase-ext .mpp
-mtune=generic -march=x86-64 -Wall -Wextra -std=gnu++23 -version -freport-bug
-fmodules-ts -fmodule-mapper=CMakeFiles/moduleMin.dir/modA.mpp.o.modmap
-fdeps-format=p1689r5 -o CMakeFiles/moduleMin.dir/modA.mpp.s
