Try to add pkg-config diagnostics

Makefile

@@ -73,6 +73,7 @@ $(if $(findstring x86_64-linux,$(3rdparty_NATIVE_ARCH)),\
 $(EXE) unit-test: private export CGO_ENABLED=1
 $(EXE) unit-test: private export PATH := $(CURDIR)/_3rdparty/tgt/bin:$(PATH)
 $(EXE): private extldflags = $(if $(findstring darwin,$(GOOS)),,-static)
+$(EXE): private export PKG_CONFIG_DEBUG_SPEW=1
 
 # Build resource files
 %_resource_windows_amd64.syso: %.rc
@@ -93,6 +94,7 @@ unit-test:
 	$(info [+] test_flags=$(test_flags) test_pathspec=$(test_pathspec))
 	$(info [+] GOROOT=$(GOROOT) GOOS=$(GOOS) GOARCH=$(GOARCH) CC=$(CC))
 	$(info [+] PKG_CONFIG_LIBDIR=$(PKG_CONFIG_LIBDIR))
+	$(info [+] PKG_CONFIG_PATH=$(PKG_CONFIG_PATH))
 	$(GOROOT)/bin/go test $(test_flags) \
 		-ldflags '-w -s -linkmode=external -extldflags "$(extldflags)"' \
 		-tags yara_static \
@@ -107,6 +109,8 @@ $(EXE):
 	$(info [+] Building spyre...)
 	$(info [+] GOROOT=$(GOROOT) GOOS=$(GOOS) GOARCH=$(GOARCH) CC=$(CC))
 	$(info [+] PKG_CONFIG_LIBDIR=$(PKG_CONFIG_LIBDIR))
+	$(info [+] PKG_CONFIG_PATH=$(PKG_CONFIG_PATH))
+	pkg-config --list-package-names
 	mkdir -p $(@D)
 	$(GOROOT)/bin/go build \
 		-ldflags '$(VERSIONDEF) -w -s -linkmode=external -extldflags "$(extldflags)"' \