Shares of Google's parent company, Alphabet, surged nearly 10 percent, while Starbucks, McDonald's and Intel also pushed higher after the companies reported solid earnings.

About 10 minutes into trading, the Dow Jones Industrial Average was up 0.1 percent at 27,170.03.

The broad-based S&P 500 climbed 0.5 percent to 3,017.37, while the tech-rich Nasdaq Composite Index jumped 0.9 percent to 8,310.25.

US government data showed second-quarter growth at 2.1 percent, slower than in the first quarter, but above expectations.

Consumer spending was a strength, offsetting weakness in business investment, said Briefing.com Patrick O'Hare, who called the report a critical input before next week's Federal Reserve meeting.

"The report won't deter the Fed from cutting the target range for the fed funds rate by 25 basis points, but it may very well have taken the prospect of a 50-basis points cut off the table," O'Hare said.

Among the other major companies reporting results, Amazon was an underperformer, reporting a 3.6 percent increase in profits to $2.6 billion which was below expectations.

Analysts said higher shipping costs needed to meet Amazon's promise of one-day delivery to Prime customers cut into profits.