diff --git a/src/test/CMakeLists.txt b/src/test/CMakeLists.txt
index 00d129c0b..eb67083c2 100644
--- a/src/test/CMakeLists.txt
+++ b/src/test/CMakeLists.txt
@@ -164,11 +164,14 @@ add_executable(test-z3
 z3_add_install_tactic_rule(${z3_test_deps})
 z3_add_memory_initializer_rule(${z3_test_deps})
 z3_add_gparams_register_modules_rule(${z3_test_deps})
-target_compile_definitions(test-z3 PRIVATE ${Z3_COMPONENT_CXX_DEFINES} Z3_TEST_SRC_DIR="${CMAKE_CURRENT_SOURCE_DIR}" Z3_TEST_BIN_DIR="${PROJECT_BINARY_DIR}")
+target_compile_definitions(test-z3 PRIVATE
+  ${Z3_COMPONENT_CXX_DEFINES}
+  Z3_TEST_SRC_DIR="${CMAKE_CURRENT_SOURCE_DIR}"
+  Z3_TEST_BIN_DIR="${PROJECT_BINARY_DIR}"
+)
 target_compile_options(test-z3 PRIVATE ${Z3_COMPONENT_CXX_FLAGS})
 target_link_libraries(test-z3 PRIVATE ${Z3_DEPENDENT_LIBS})
 target_include_directories(test-z3 PRIVATE ${Z3_COMPONENT_EXTRA_INCLUDE_DIRS})
 z3_append_linker_flag_list_to_target(test-z3 ${Z3_DEPENDENT_EXTRA_CXX_LINK_FLAGS})
 z3_add_component_dependencies_to_target(test-z3 ${z3_test_expanded_deps})
 add_dependencies(test-z3 shell)
-
diff --git a/src/test/tptp.cpp b/src/test/tptp.cpp
index f1558a08d..bb9c6d0a5 100644
--- a/src/test/tptp.cpp
+++ b/src/test/tptp.cpp
@@ -2,6 +2,8 @@
 #include <sstream>
 #include <string>
 #include <vector>
+#include <cctype>
+#include <iostream>
 #include "util/debug.h"
 
 #ifdef _WINDOWS
@@ -20,16 +22,33 @@ struct tptp_case {
     char const* expected_status;
 };
 
-constexpr unsigned tptp_buf_sz = 4096;
+constexpr unsigned tptp_buffer_size = 4096;
+
+static bool is_safe_file_name(char const* s) {
+    while (*s) {
+        unsigned char c = static_cast<unsigned char>(*s);
+        if (!(std::isalnum(c) || c == '.' || c == '-' || c == '_'))
+            return false;
+        ++s;
+    }
+    return true;
+}
 
 static std::string run_tptp(char const* file) {
+    if (!is_safe_file_name(file)) {
+        std::cerr << "Unsafe TPTP test filename: " << file << "\n";
+        ENSURE(false);
+    }
     std::ostringstream cmd;
     cmd << "\"" << Z3_TEST_BIN_DIR << "/" << z3_bin_name << "\" -tptp "
         << "\"" << Z3_TEST_SRC_DIR << "/tptp/" << file << "\" 2>&1";
     FILE* pipe = Z3_POPEN(cmd.str().c_str(), "r");
-    ENSURE(pipe != nullptr);
+    if (!pipe) {
+        std::cerr << "Failed to execute command: " << cmd.str() << "\n";
+        ENSURE(false);
+    }
     std::string out;
-    char buffer[tptp_buf_sz];
+    char buffer[tptp_buffer_size];
     while (fgets(buffer, sizeof(buffer), pipe))
         out += buffer;
     int code = Z3_PCLOSE(pipe);
@@ -37,7 +56,11 @@ static std::string run_tptp(char const* file) {
     if (WIFEXITED(code))
         code = WEXITSTATUS(code);
 #endif
-    ENSURE(code == 0);
+    if (code != 0) {
+        std::cerr << "TPTP command failed for file '" << file << "' with exit code " << code << "\n";
+        std::cerr << out << "\n";
+        ENSURE(false);
+    }
     return out;
 }