SIGSEGV, Segmentation fault, during runtime execution on arm (CortexA9) - c

Question

What I do
I'm building go application that should be run on CortexA9 CPU and uses 3 different C/C++ shared libraries (I use C wrapper to call C++ code), when calling one of them (Clips rules engine http://www.clipsrules.net/) I accidentally get SIGSEGV, Segmentation fault, the library itself is quite old and well tested, also the same code works well on amd64 arch. The place where error occurs looks quite random, if I rewrite code to avoid the specific code lines, it will occur in the middle of an other function.
How I build lib
I use arm-buildroot-linux-gnueabi toolchain and arm-buildroot-linux-gnueabihf-gcc as C compiler, so is built with this CFLAGS: -Wall -std=c99 -O3 -fno-strict-aliasing -fPIC -march=armv7-a -mcpu=cortex-a9 -mfpu=neon -mfloat-abi=hard --sysroot=${some path}
If I build Clips as standalone binary (with this toolchain) and run some rules on it, it works well.
How I build golang app
I build app on docker golang:1.16-buster, where my toolchanin is placed
go clean && env CGO_CFLAGS="-march=armv7-a -mfpu=neon -mfloat-abi=hard -mtune=cortex-a9 --sysroot={soem path}" CGO_ENABLED=1 GOOS="linux" GOARM=7 GOARCH=arm go build --tags=with_libs,arm -o ./out/$app_name .
CC is set to arm-buildroot-linux-gnueabihf-gcc
To add library to project I have arm.go file:
// +build arm
package clips
// #cgo LDFLAGS: -L../../libs/arm -lclips -lm -Wl,-rpath -Wl,../libs/arm
import "C"
What did you expect to see?
I expect to see no unexpected signals.
What did you see instead?
While app is running, when I perform cgo calls from so library I get this (from gdb):
Thread 1 "myapp-arm" received signal SIGSEGV, Segmentation fault.
gdb: backtrace:
#0 0x76d6fa6c in PrintTemplateFact (theEnv=0x4c8b90, logicalName=0x76d79184 "FactPPForm", theFact=0x4c6dd8, seperateLines=0, ignoreDefaults=0) at /myapp/clips_source/tmpltutl.c:387
#1 0x76cbfa70 in PrintFact (theEnv=0x4c8b90, logicalName=0x76d79184 "FactPPForm", factPtr=0x4c6dd8, seperateLines=0, ignoreDefaults=0) at /myapp/clips_source/factmngr.c:445
#2 0x76cbf704 in PrintFactWithIdentifier (theEnv=0x4c8b90, logicalName=0x76d79184 "FactPPForm", factPtr=0x4c6dd8) at /myapp/clips_source/factmngr.c:328
#3 0x76cc1950 in EnvGetFactPPForm (theEnv=0x4c8b90, buffer=0x535290 "f--1 (attribute (id ) (comment ) (code ) (path", bufferLength=1023, theFact=0x4c6dd8) at /myapp/clips_source/factmngr.c:1590
#4 0x002661e8 in _cgo_4cadad88d928_Cfunc_EnvGetFactPPForm ()
#5 0x000823d8 in runtime.asmcgocall () at /usr/local/go/src/runtime/asm_arm.s:596
#6 0x00a16050 in ?? ()
gdb disas:
...
0x76d6fa3c <+616>: mov r2, r1
0x76d6fa40 <+620>: ldr r1, [r11, #-60] ; 0xffffffc4
0x76d6fa44 <+624>: ldr r0, [r11, #-56] ; 0xffffffc8
0x76d6fa48 <+628>: bl 0x76c68edc <PrintAtom#plt>
0x76d6fa4c <+632>: b 0x76d6fad0 <PrintTemplateFact+764>
0x76d6fa50 <+636>: ldr r3, [r11, #-8]
0x76d6fa54 <+640>: lsl r3, r3, #3
0x76d6fa58 <+644>: ldr r2, [r11, #-24] ; 0xffffffe8
0x76d6fa5c <+648>: add r3, r2, r3
0x76d6fa60 <+652>: ldr r3, [r3, #4]
0x76d6fa64 <+656>: str r3, [r11, #-28] ; 0xffffffe4
0x76d6fa68 <+660>: ldr r3, [r11, #-28] ; 0xffffffe4
=> 0x76d6fa6c <+664>: ldr r3, [r3, #4]
0x76d6fa70 <+668>: cmp r3, #0
0x76d6fa74 <+672>: ble 0x76d6fad0 <PrintTemplateFact+764>
0x76d6fa78 <+676>: ldr r3, [pc, #232] ; 0x76d6fb68 <PrintTemplateFact+916>
0x76d6fa7c <+680>: add r3, pc, r3
0x76d6fa80 <+684>: mov r2, r3
0x76d6fa84 <+688>: ldr r1, [r11, #-60] ; 0xffffffc4
0x76d6fa88 <+692>: ldr r0, [r11, #-56] ; 0xffffffc8
0x76d6fa8c <+696>: bl 0x76c68c3c <EnvPrintRouter#plt>
0x76d6fa90 <+700>: ldr r3, [r11, #-8]
...
EDIT:
I can even get SEGFAULT with this code:
func SelfHealthCheck(deftemplate string) {
env := C.CreateEnvironment()
// Create deftemplate
cconstruct := C.CString(deftemplate)
defer C.free(unsafe.Pointer(cconstruct))
if C.EnvBuild(env, cconstruct) != 1 {
log.Println("error")
return
}
// Obtain pointer on it
cname := C.CString("attribute")
defer C.free(unsafe.Pointer(cname))
tplptr := C.EnvFindDeftemplate(env, cname)
if tplptr == nil {
log.Println("error")
return
}
// Create fact
factptr := C.EnvCreateFact(env, tplptr)
// print it
var bufsize C.size_t = 1024
buf := (*C.char)(C.malloc(C.sizeof_char * bufsize))
defer C.free(unsafe.Pointer(buf))
C.EnvGetFactPPForm(env, buf, bufsize-1, unsafe.Pointer(factptr))
log.Infoln(C.GoString(buf))
}