diff --git a/dist/gcc_matcher.jsontemplate b/dist/gcc_matcher.jsontemplate
index 9019aee..0e2dac5 100644
--- a/dist/gcc_matcher.jsontemplate
+++ b/dist/gcc_matcher.jsontemplate
@@ -4,7 +4,7 @@
             "owner": "gcc-problem-matcher",
             "pattern": [
                 {
-                    "regexp": "^(${{ BASE }})(.*?):(\\d+):(\\d*):?\\s+(?:fatal\\s+)?(warning|error):\\s+(.*)$",
+                    "regexp": "^(${{ BASE }}\\/?)(.*?):(\\d+):(\\d*):?\\s+(?:fatal\\s+)?(warning|error):\\s+(.*)$",
                     "fromPath": 1,
                     "file": 2,
                     "line": 3,
diff --git a/dist/index.js b/dist/index.js
index ab975fa..cae0340 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -2848,7 +2848,7 @@ const core = __nccwpck_require__(127);
 // escapeRegExp :: string => string
 // escape all characters with special meanings in regexp
 const escapeRegExp = (s) =>
-	s.replace(/[/\-^$*+?.()|[\]{}]/g, "\\$&");
+	s.replace(/[/\-^$*+?.()|[\]{}]/g, "\\\\$&");
 
 // variable :: string => RegExp
 // create regex to match ${{ key }}
@@ -2859,7 +2859,7 @@ const variable = (key) =>
 const templatePath = __nccwpck_require__.ab + "gcc_matcher.jsontemplate";
 
 // matcherPath :: string
-const matcherPath = __nccwpck_require__.ab + "gcc_matcher.json";
+const outputPath = __nccwpck_require__.ab + "gcc_matcher.json";
 
 // rootdir :: string
 const rootdir = core.getInput('build-directory', {required: false});
diff --git a/src/gcc_matcher.jsontemplate b/src/gcc_matcher.jsontemplate
index 9019aee..0e2dac5 100644
--- a/src/gcc_matcher.jsontemplate
+++ b/src/gcc_matcher.jsontemplate
@@ -4,7 +4,7 @@
             "owner": "gcc-problem-matcher",
             "pattern": [
                 {
-                    "regexp": "^(${{ BASE }})(.*?):(\\d+):(\\d*):?\\s+(?:fatal\\s+)?(warning|error):\\s+(.*)$",
+                    "regexp": "^(${{ BASE }}\\/?)(.*?):(\\d+):(\\d*):?\\s+(?:fatal\\s+)?(warning|error):\\s+(.*)$",
                     "fromPath": 1,
                     "file": 2,
                     "line": 3,
diff --git a/src/index.js b/src/index.js
index b58216e..6ff6211 100644
--- a/src/index.js
+++ b/src/index.js
@@ -5,7 +5,7 @@ const core = require('@actions/core');
 // escapeRegExp :: string => string
 // escape all characters with special meanings in regexp
 const escapeRegExp = (s) =>
-	s.replace(/[/\-^$*+?.()|[\]{}]/g, "\\$&");
+	s.replace(/[/\-^$*+?.()|[\]{}]/g, "\\\\$&");
 
 // variable :: string => RegExp
 // create regex to match ${{ key }}
@@ -16,7 +16,7 @@ const variable = (key) =>
 const templatePath = path.join(__dirname, "gcc_matcher.jsontemplate");
 
 // matcherPath :: string
-const matcherPath = path.join(__dirname, "gcc_matcher.json");
+const outputPath = path.join(__dirname, "gcc_matcher.json");
 
 // rootdir :: string
 const rootdir = core.getInput('build-directory', {required: false});
@@ -34,7 +34,7 @@ const parse = (templatePath) => (matcherPath) => {
 
 // main:
 try {
-	parse(templatePath)(matcherPath);
+	parse(templatePath)(outputPath);
 } catch (err) {
 	core.setFailed(`Action failed with error ${err}`)
 }